A stunning photo from Stefanos Tstitsipas' training session ahead of his match against big server John Isner has taken the tennis world by storm.
Tsitsipas advanced to the Round of 16 after a four-set victory over Isner at Roland Garros.
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But he might be able to thank some unusual training methods for the extra-leg up.
The World No.5 was seen practising his return of serve, but his partner had moved up into the court to try and replicate his next opponent's huge serve.
New York Times reporter Christopher Clarey explained the process: "How did Tsitsipas prepare to return Isner's monster serve tonight?"
"Had his practice partner serve from close to the service box."
The unique training method to acclimatise to the American's monster serve appeared to work after yet another barnstorming performance from the in-form World No.5.
Tsitsipas keeps up clay court form
Tsitsipas has impressed on the European clay court swing this season — lifting his first ATP Masters title in Monte Carlo followed by another trophy in Lyon — and has more wins on the surface than any other player in 2021.
The 22-year-old was tested by American John Isner in the third round on Friday before he emerged victorious in four sets but Spain's Carreno Busta has also enjoyed an impressive spell on the red dirt in the lead up to the Paris major.
The 12th seed won an ATP 250 event in Marbella before making a run to the semi-finals in Barcelona — where he was beaten by Rafa Nadal.
"I think that my level is going up," said Carreno Busta, who has previously made two quarter-final appearances at Roland Garros. "Tsitsipas I think is leading the Race to Turin. So it will be interesting match. Very tough, for sure."
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