Why is Zverev allowed to use his phone at Wimbledon?

Many of you have been in touch to ask why Alexander Zverev has been seen using his phone multiple times during matches at this year's Wimbledon - despite a ban on players doing so.

The reason is because Zverev is type 1 diabetic, and therefore has a medical exemption from the rule in order to check his glucose levels.

The All England Club has told BBC Sport that Grand Slam tournaments have a list of players that are diabetic, and those players are permitted to use their phones during matches in order to monitor their glucose and inject insulin if needed.

Zverev, who has reached the men's singles final, told BBC Sport he has two phones, one of which contains no SIM card as it is solely used for monitoring his glucose while on court.

It means he can simply read the levels that his glucose monitor is relaying to his phone screen, instead of doing constant finger-prick checks.

“That’s why the umpires allow me to check my phone, so I don’t have to poke my finger every changeover,” he said.

A malfunction with Zverev's monitor during the Halle Open in June led to him injecting a much higher level of insulin than needed during his semi-final loss to Taylor Fritz.

He said the mistake left him feeling "absolutely terrible" as he had to consume about 350g of sugar to counteract the high dose of insulin.