World number seven and defending champion Alexander Zverev has denied using his phone in his loss to Stefanos Tsitsipas during the round-robin of the ATP Finals on Thursday.
The 22-year-old made headlines during his opening match after his stunning defeat of world number one Rafael Nadal on Monday.
He would fail to back it his impressive form against the Greek superstar, going down 6-3 6-2.
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However, all the attention after the match turned to his apparent use of a mobile phone during the second set of the match.
TV cameras appeared to show a device on his bag light up whilst he was scrolling through it, which led to social media questioning whether the German had broken ATP rules regarding the use of technological devices on-court.
Zverev was not particularly slick about the phone use either. He’s down a double break in this set, so it hasn’t much helped. pic.twitter.com/9aLb8TL1QN
— Ben Rothenberg (@BenRothenberg) November 13, 2019
Does Zverev keep checking his phone while on court this week? 😳
— Ryan 🐨 (@Ryanroxs01) November 13, 2019
The incident divided fans, with many arguing that he was using a dexcom monitor to check his insulin levels.
Zverev really said he was looking at a water bottle in his bag and not his phone, yet on two occasions his whole damn hand lit up 🤡
— Tanis (@Tanis95) November 13, 2019
Here is Zverev the cheater checking his Dexcom monitor in Beijing .The ATP need to fine and ban him immediately HE CANT KEEP GETTING AWAY WITH THIS pic.twitter.com/X1XtHOLYWZ
— dkdqdwk (@ffffyaahehe) November 13, 2019
It’s well known that he’s diabetic, there’s publicly available footage/pictures of him checking his blood sugar and using a Humalog KwikPen in practice. So he was probably checking his sugar levels.
— Minh L (@vngbusa) November 13, 2019
Entirely possible that Zverev is indeed using some phonelike-but-not-a-phone electronic device. But if it’s a legal, approved thing, weird to keep it low and hidden and deny any knowledge of the device when asked. https://t.co/1tfW99rcGX
— Ben Rothenberg (@BenRothenberg) November 13, 2019
When asked about the incident, Zverev was clueless towards the accusations, suggesting that he was playing with a empty water bottle in his bag.
“My phone? My phone was in the locker room actually,” he said during his post-match press conference
"I always leave it there,
"I don't know what they saw but it was definitely not a phone.
"I mean, a water bottle?
"Empty water bottle maybe?"
Zverev will be looking to book his place in the semi-final when he takes on Russian Danii Medvedev on Friday, who suffered a dramatic loss to Nadal after leading 5-1 in the final set.