World number 10 Matteo Berrettini has been forced to retire from the Australian Open after failing to overcome an abdominal injury.
Berrettini had looked in exceptional shape and form during the competition so far, but he broke down during the third set of his third round match against Karen Khachanov on Friday.
He was able to continue playing and won a decisive tiebreaker to win the match in straight sets, although the injury has ultimately put an end to his tournament.
Berrettini seemed hopeful after he did the injury, telling Eurosport he 'felt something go' although he was told it was not a pulled muscle.
"I don’t know what happened, I felt here under my rib something that pulled, but the physio said that nothing was pulled,” he explained.
“It could be some muscle that wasn’t working properly. But I was really feeling it when I was serving and then obviously my mindset went a little bit away because I was thinking about it.
"I was two sets up, I was playing good, I was feeling the momentum, then all of a sudden I felt this.
“I’m really glad I could win the third set, now I have to do a great job with my physio to get back on court in two days.”
Stefanos Tsitsipas will now receive a walkover and face Rafael Nadal in the quarterfinals on Wednesday.
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