MLB post-hype check-in: What to make of former big...

David SchoenfieldJun 5, 2026, 07:00 AM ET

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Former deputy editor of Page 2

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Players like Corbin Carroll, Paul Skenes, Nick Kurtz and now Kevin McGonigle have spoiled it for all hyped Major League Baseball prospects in recent years: We expect instant stardom from them, forgetting that baseball, as the great Jimmy Dugan once said, is "supposed to be hard. If it wasn't hard, everyone would do it."

This is especially true for young hitters, who face one pitching wizard after another followed by some sorcerer chucking invisible sliders followed by a diabolical closer throwing 102 mph in the ninth inning.

It's not easy, which means many top prospects don't burst out of the gate as polished players. Jordan Walker is the latest example of that, finally breaking out in his fourth season in the majors -- and still just 24 years old.

Let's do a post-hype check-in on a dozen interesting young players who are still looking to put it all together. We'll break them into tiers based on their success so far.

Tier I: Showing success

Kyle Harrison, LHP, Milwaukee Brewers

Peak ESPN prospect ranking: No. 19 (2023)

Background: A third-round pick out of high school by the San Francisco Giants in 2020, Harrison blitzed through the minors and reached the majors with a seven-start call-up in 2023. He had a solid, if unspectacular, rookie season in 2024, going 7-7 with a 4.56 ERA in 24 starts. He struggled in spring training in 2025, went to the Boston Red Sox in the Rafael Devers trade, pitched just 12 innings in the majors for them and then was traded to the Brewers in the Caleb Durbin deal this past offseason.

2026: 7-1, 1.57 ERA, 57⅓ IP, 43 H, 16 BB, 73 SO

Harrison certainly landed with the right team, as the Brewers develop pitchers as well as any organization. Indeed, this script looks familiar. Just a year ago, the Brewers acquired Quinn Priester -- a former top prospect with the Pittsburgh Pirates -- from the Red Sox, and Priester went on to have a breakout season. Now, they've acquired Harrison (and fellow lefty Shane Drohan) from the Red Sox in what looks like one of the best deals of the offseason.

It's just 11 starts, but Harrison's breakout appears legit so far. He's throwing strikes: Among pitchers with at least 50 innings pitched, he's third in strikeout rate at 31.9%. He had a string of three straight scoreless starts to finish May -- as he and teammate Jacob Misiorowski combined to go 9-0 in the month with eight scoreless outings -- and then struck out 12 in his first start of June. He seems to be getting better rather than the league figuring him out.

Harrison's improvement from his rookie season is easy to identify. His fastball velocity is up from 92.6 mph to 95 and he's using it to get ahead of hitters. His slurve averages almost 11 inches of glove-side horizontal break with a ton of depth, and batters are hitting .115 against it. He throws those two pitches 88.6% of the time. He did miss time in 2024 with shoulder inflammation, which may have affected his velocity that season, but a vital change has been raising his arm angle from 24 degrees in 2024 to 33 degrees in 2026.

That has helped him maintain a more consistent delivery, including "being on time and understanding what that means," Harrison explained in an interview with MLB Network last week.

The two-pitch combo is working its magic: The Statcast run value on his fastball ranks in the 95th percentile of all pitchers and the run value on his breaking ball ranks in the 96th percentile. It looks like a lethal one-two punch brewing in Milwaukee.

Chandler Simpson, LF, Tampa Bay Rays

Peak ESPN prospect ranking: No. 91 (2025)

Background: After two years at Alabama-Birmingham, Simpson transferred to Georgia Tech for his draft season in 2022 and led the ACC with a .433 average while striking out just 16 times in 241 plate appearances. With just one home run, however, he was a divisive prospect, but the Rays plucked him in the second round. He hit .295/.326/.345 with 44 steals as a rookie in 2025 and is producing similar numbers this season.

2026: 58 G, .274/.307/.326, 0 HR, 14 SB

Simpson is undoubtedly one of the most exciting players in baseball, using his speed to beat out infield grounders and taking every extra bag possible while running the bases. When he swings, he makes contact -- only three players have a higher contact rate -- and contact for Simpson is the driving force of his offensive game. After struggling in center field as a rookie, his defensive metrics in left field have been outstanding.

The question: How valuable is the whole package? He has no power and doesn't walk much -- indeed, the Simpson-type player has largely been drummed out of baseball in recent years, mostly because those types struggle to hit velocity. Simpson hit .314 with a .349 OBP in April, and that's a really nice player when you factor in his defense. When he hit .245 with a .278 OBP in May, however, he looked more like a defensive replacement/pinch runner.

Still, Simpson had 0.9 WAR through the end of May, putting him on pace for close to 3 WAR on the season, which would make him an above-average regular. It's a fine line though. We should all want Simpson to succeed; the more diversity in the style of play, the more entertaining the game. Let's hope he finds that April level of productivity the rest of the way.

Tier II: Success ... and then some bumps

Jackson Merrill, CF, San Diego Padres

Peak ESPN prospect ranking: No. 12 (2024)

Background: A pop-up prospect in the spring of 2021 out of a Maryland high school, the Padres took him late in the first round with the 27th pick of that summer's draft. A shortstop in the minors, Merrill cracked the Opening Day roster in 2024 as a center fielder and had a remarkable rookie season at age 21, producing 4.8 WAR and handling the defensive change with ease. His numbers have gone backward since then, however, with an especially slow start to this season.

2026: 58 G, .207/.280/.341, 6 HR, 10 SB

This is a strange one. Merrill was perhaps rushed to the majors in 2024 after just 200 games in the minors, but he justified the decision with that superlative 24-homer rookie season, matching Roberto Alomar for the highest age-21 season WAR in Padres history. Merrill looked on his way to becoming one of the top stars in the game.

His offense dropped off in 2025, from an 0.826 OPS to .774, although three stints on the injured list -- hamstring, concussion, sprained ankle -- undoubtedly played a role. He's scuffling through the first two months of 2026, however, although maybe a three-hit game Sunday will get him going. He has been somewhat unlucky according to Statcast, with a wOBA around 50 points lower than his expected wOBA based on his contact quality.

The concern with Merrill has always been a high chase rate -- above 34% all three seasons in the majors (the MLB average is 28.6% over the three years) -- and maybe pitchers learning to exploit that helps explain why his strikeout rate has increased from his rookie season. Like teammate Fernando Tatis Jr., Merrill has also been too ground ball happy in 2026, leading to a lot of routine 4-3 putouts. One number that jumps out: His slugging percentage against fastballs was .510 as a rookie and is around .350 in 2026 while his contact rate has fallen from 81.4% to 71.6%.

The talent is here -- you can't be as good as Merrill was at 21 and not have loads of it -- but the swing decisions need to improve and he has to start mashing fastballs again.

Evan Carter, CF, Texas Rangers

Peak ESPN prospect ranking: No. 6 (2024)

Background: Even though Carter had a commitment to Duke coming out of high school, he was a huge surprise as a second-round pick in 2020, as he had skipped most of the showcase events and had little exposure to most of the scouting industry. Rangers area scouts Derrick Tucker and Ryan Coe saw enough to select him, and Carter's advanced hitting skills helped him reach the majors in September of 2023. He then went on to post a 1.058 OPS in 23 games and .917 in the postseason as the Rangers won the World Series.

2026: 59 G, .171/.291/.331, 6 HR, 9 SB

In retrospect, maybe Carter's ridiculous exploits in September and October of 2023 created unrealistic expectations. After all, he hit better in the majors than he had in the minors that season. Still, he looked as safe as any hitting prospect in recent years with elite knowledge of the strike zone and a pretty left-handed line-drive stroke.

However, it's been a grind since then. Three things working against him:

He has struggled against left-handers, hitting .069 in his career (1-for-27 in 2026).

Globe Life Field has turned into one of the toughest hitter's parks in the majors and Carter's OPS is 100 points higher on the road over the past two seasons.

Injuries.

The last one is big. He played just 108 games in 2024-25 because of back problems, a quad strain and a broken wrist that ended his 2025 season in August. It's not just the injuries affecting his performance, but the crucial lost development time for a young hitter.

His swing is also different though: more loft than when he first came up, so more fly balls and fewer line drives. Keep in mind: He's still just 23 years old with fewer than 700 plate appearances. One promising development is that he has turned into a plus-plus defender in center field. He has also maintained his excellent strike zone judgment, with a 96th percentile chase rate. Plate discipline is so vital to a hitter's success that there is still hope Carter will turn it around, but you have to wonder if he needs to get back to more of a gap-to-gap approach.

Cam Smith, RF, Houston Astros

Peak ESPN prospect ranking: No. 73 (2025)

Background: Following an explosive season at Florida State in 2024, the Chicago Cubs drafted Smith 14th and then made him the centerpiece in the Kyle Tucker trade that offseason. Despite playing just 32 games in the minors, Smith made the Opening Day roster for the Astros in 2025 and had an 0.805 OPS in early July. It's been harder going since that early success.

2026: 62 G, .216/.307/.351, 6 HR, 8 SB

You often hear analysts on local broadcasts saying that players are rushed to the majors quicker than ever. I don't think that's actually true -- something to study! -- but in Smith's case, this does feel like a developmental misstep by the Astros, putting him in the majors after just two years in college and hardly any time in the minors. Smith hit .153 over his final 59 games as a rookie, and after a good start to the 2026 season, he has hit under .200 since mid-April.

The tools are obvious: one of the quickest bats in the majors, plus-plus speed and a strong arm. (He might be the best right fielder in the majors already, after playing third base for the Seminoles.) The Astros bet on that athleticism, but perhaps not surprisingly, Smith continues to struggle against breaking balls and off-speed pitches. Like Merrill and Carter, though, Smith is still just 23 years old. As Walker has shown, the learning curve can sometimes take years. Let's put it this way: If Smith does figure things out, he might have more upside to his offensive game than Merrill or Carter.

Jasson Dominguez, LF, New York Yankees

Peak ESPN prospect ranking: No. 21 (2024)

Background: One of the most ballyhooed international signings in history, the Yankees signed Dominguez in July of 2019 to a $5.1 million bonus at age 16 -- by which time the switch-hitting phenom had already earned the nickname "The Martian." He debuted in the majors in 2023 at age 20, missed part of 2024 recovering from Tommy John surgery and then hit .257/.331/.388 in 123 games as a rookie in 2025.

2026: 9 G, .200/.250/.367, 1 HR, 0 SB

Another theory: The most overrated prospects are those who are physically mature as teenagers. Dominguez's switch-hitting power and speed stood out compared with other players his age. As Kiley McDaniel wrote in 2020, "Some scouts say he's the best 16-year-old baseball player they've ever seen." But he also offered little physical projection, so maybe that hype was unfair to a young kid. Dominguez methodically moved through the minors, always young for his league and performing well -- although not so well that he ever cracked the top 20 prospects, despite appearing on Kiley's preseason top 100 six times.

As a rookie, Dominguez hit well against right-handers (.768) and hit well overall in the first half (.760 OPS), but as his offense declined, his playing time diminished in the final two months of the 2025 season and he found himself coming off the bench in the playoffs. When Trent Grisham accepted the qualifying offer and Cody Bellinger re-signed, Dominguez was left without a regular role, so the Yankees optioned him to Triple-A to begin the season. They praised how he handled the demotion, he hit well at Scranton and he was called up in late April when Giancarlo Stanton was injured. Unfortunately, Dominguez soon thereafter crashed into the outfield wall while making a catch and sprained his shoulder, landing on the IL.

So where does that leave us? It's anyone's guess. The Yankees have said Dominguez remains part of the long-term plans. Part of the problem is his defense in left field last year was not good, so he's not the center fielder of the future as they once envisioned. The likeliest path at this point is that Grisham departs after this season, Bellinger shifts to center and Dominguez plays left. He'll still be just 24 years old at the start of the 2027 season, and though the out-of-this-world expectations are long gone, he can still turn into an above-average hitter.

Jackson Holliday, 2B, Baltimore Orioles

Peak ESPN prospect ranking: No. 1 (2024)

Background: The first overall pick in 2022, Holliday topped all prospect lists after a huge age-19 season across three levels of the minors in 2023 when he hit .323/.442/.499 with 12 home runs and 101 walks. Called up early in 2024, he struggled, was sent back down to Triple-A and ended up hitting .189 in 60 games for the Orioles. In his first full season in 2025, he hit .242/.314/.375 with 17 home runs, but his OPS declined from .722 in the first half to .642 in the second.

2026: 14 G, .231/.340/.385, 2 HR, 3 SB

It's one thing to see pitchers going down, but all these injuries to young position players across the league are also concerning. Holliday fractured his hamate bone early in spring training and only recently returned. A year ago, similar to Smith and Dominguez, Holliday hit better in the first half before tailing off after the All-Star break -- and you obviously want to see young players improving rather than sliding backward.

Holliday's scouting reports are now a grade or two lower than in 2023, with the hit tool in particular taking a dip. His bat speed last year was well below average, and Holliday didn't compensate with enough contact (140 strikeouts). Pitchers were beating him with fastballs, so even though he showed strong plate discipline, they could still attack him when behind in counts. His range metrics at second base were also poor.

Again, note his age: He's still just 22 years old. The hope is the baseball "gene" he inherited from father Matt will kick in with additional experience, but his ceiling certainly appears lower than the Orioles had hoped it would be a few years ago -- more of a good player in the long run than a regular All-Star.

Tier III: The jury is out

Roki Sasaki, RHP, Los Angeles Dodgers

Peak ESPN prospect ranking: No. 1 (2025)

Background: A teenage phenom in Japan, Sasaki reached 101 mph in high school; had a 1.84 ERA at age 19 in the Japanese Pacific League; threw a perfect game at age 20 in 2022, in which he struck out 19 batters (including 13 in a row); and then came over to MLB following the 2024 season. With his upper-90s fastball and a splitter viewed as perhaps the best in baseball, he was seen as an eventual ace-caliber starting pitcher after signing with the Dodgers.

2026: 3-3, 4.59 ERA, 51 IP, 50 H, 19 BB, 50 SO

The future for Sasaki is perhaps more mysterious than any player on this list. He could still turn into an ace, a closer or anything in between. With all the injuries to the Dodgers' rotation, he opened the 2026 season in the rotation -- despite becoming L.A.'s closer last October -- with the smart approach giving him a multiyear opportunity to prove himself as a starter.

Sasaki pitched better in May after a pretty putrid April, when he struggled with home runs and walks. He throws 97 mph but his fastball is straight and hitters have teed off on it with a .597 slugging percentage. He has gone from using a sweeper last season to more of a slider this year and it's been an effective pitch for him, at least giving him a third pitch and different look. As long as his fastball remains so hittable, however, he won't be anything more than a back-end starter, no matter how good the splitter is.

Dylan Crews, OF, Washington Nationals

Peak ESPN prospect ranking: No. 5 (2024)

Background: One of the most decorated players in college baseball history, Crews won back-to-back SEC Player of the Year honors and hit .426/.567/.713 with 18 home runs and 71 walks in 71 games at LSU in 2023. He and teammate Paul Skenes were the consensus top two players in the draft and there was much debate about who should go No. 1. The Pirates took Skenes and the Nationals followed with Crews.

2026: 13 G, .208/.255/.292, 1 HR, 1 SB

This has been one of the most surprising developments in recent years, as Crews projected as one of the most polished, ready-for-the-majors college hitters in a long time. He just hasn't hit as expected -- either in the minors or in his 500 plate appearances spread across three seasons in the majors. After hitting .208 for the Nationals in 2025, Crews began this season at Triple-A Rochester, where he hit a so-so .258/.345/.432 before getting called up to the majors.

His in-zone contact rates have been fine and his strikeout rates are right at the MLB average, but he has had trouble getting the ball in the air, especially to the pull side, so the damage on contact has been limited. While he's not chasing excessively out of the strike zone, he also hasn't walked much, and that looked like a strength coming out of LSU. Crews can run and has played good defense, but right now he's profiling as a fourth outfielder instead of the foundational player the Nationals expected when they drafted him.

Marcelo Mayer, 2B/SS, Boston Red Sox

Peak ESPN prospect ranking: No. 4 (2025)

Background: Considered by many scouts the top talent in the 2021 draft as a San Diego-area high school player, Mayer fell to the Red Sox with the fourth selection. He spent the next four years high atop prospect lists despite missing time with injuries in 2022, 2023 and 2024. He debuted with the Red Sox last year, hitting .228/.278/.402 in 44 games, and has been their regular second baseman in 2026.

2026: 55 G, .222/.283/.296, 2 HR, 3 SB

Yes, another player who has been hit with injuries, as Mayer didn't reach 100 games in any of his four full professional seasons heading into 2026. Always projected as a plus defender at shortstop with bat speed and power potential, he has mostly played second base since reaching the majors with veteran Trevor Story entrenched at shortstop. That's been a questionable decision by the Red Sox given Story's subpar defensive metrics the past two seasons. Mayer has been getting a chance to play there recently with Story sidelined with a hernia; we'll see how manager Chad Tracy plays it when Story returns. The Red Sox have also limited Mayer's at-bats against lefties, essentially making him a platoon player, another questionable decision for a highly rated prospect.

At the plate, it's too soon to pass judgment as Mayer has just over 300 plate appearances, but the early returns haven't been great. He struggled with strikeouts last season (41 K's against just eight walks), and though he has improved in that area in 2026 with a strikeout rate below 20%, he's not driving the ball with much authority, despite 80th percentile bat speed. Out of 306 players this season with at least 100 PAs, he ranks south of 250th in average exit velocity.

Maybe this is still an adjustment period. First, more contact; next, better contact. It's also not obvious that Mayer is a sure-bet plus defender at shortstop as his arm strength is well below average -- and his future there also might be in question with Franklin Arias on the rise in the minors. I think there's still more upside here, although Mayer needs to prove he can stay healthy.

Coby Mayo, 3B, Baltimore Orioles

Peak ESPN prospect ranking: No. 8 (2025)

Background: A fourth-round pick in 2020 out of Marjory Stoneman Douglas High School in Parkland, Florida, the school that produced Anthony Rizzo (and later Roman Anthony), Mayo emerged as a Rizzo-type power-hitting prospect, hitting 29 home runs in 2023 and then 25 in 93 games in 2024. He struggled in his initial call-up to the Orioles that year, going 4-for-41, and then hit .217/.299/.388 with 11 home runs in 85 games as a rookie in 2025.

2026: 50 G, .203/.272/.379, 7 HR, 1 SB

The positives: He hits the ball hard (87th percentile exit velo, 83rd percentile hard-hit rate), has demonstrated a solid approach (51st percentile chase rate), has a swing geared to lift the ball, and has mashed left-handers (1.013 OPS this season). If you're optimistic, you can still see the potential for a top-flight power hitter.

The negatives: He has struggled against breaking balls and off-speed pitches (.169 average), which in turn has led to a lot of swing-and-miss, especially against right-handers (.155 average, .468 OPS). His defense at third base suggests -- as projected as a prospect -- that he's a first baseman. Bottom line: Short-side platoon first basemen don't really have a role in this era of baseball. Mayo is going to have to learn to hit right-handed pitching.

Jac Caglianone, RF, Kansas City Royals

Peak ESPN prospect ranking: No. 29 (2025)

Background: A two-way star at the University of Florida, where he earned the nickname "Jactani" in 2023 and hit .419 with 35 home runs while going 5-2 as a pitcher and throwing in the upper 90s the following season, the Royals were ecstatic to land Caglianone with the sixth pick. He focused on hitting and the hype reached a fever pitch after he tore through the upper minors in the first two months of 2025. The Royals called him up in early June, but in 62 games in the majors, he hit just .157 with seven home runs.

2026: 58 G, .245/.319/.396, 6 HR, 2 SB

Hmm, maybe players are being rushed to the majors, as Caglianone was called up after just 100 games in the minors and the Arizona Fall League. He hit .147 through his first 41 games with the Royals last season, necessitating a return to Triple-A. Here's a fun fact to consider though: Through his first 213 games in the majors, Bobby Witt Jr. hit .248/.286/.423. Then, midway through June of his second season, it suddenly clicked. Note Caglianone's batting line so far in 2026 -- it's pretty similar to Witt's line before his breakout.

Like Witt, we're talking off-the-charts tools, with 95th percentile bat speed and a 99th percentile hard-hit rate in 2026. Few batters can crush a baseball like Caglianone can when he squares one up. The problems have been a high swing-and-miss rate (although Witt is only average in that department, even to this day) and, somewhat surprisingly given all the home runs Caglianone hit in college, an inability to hit the ball in the air more often, which explains the pedestrian major league home run total despite the hard contact. It might eventually require some mechanical tweaks, but Caglianone's power potential remains elite and it's way too early to write off his potential stardom. It wouldn't be a shock if he ends up the best hitter among the players included here.