Stefanos Tsitsipas stunned by Jack Draper in dramatic Cincinnati comeback

Draper had required a medical time out during his first-round win over Jaume Munar, but appeared to be moving freely during the early exchanges.

Tsitsipas made a decisive break to lead 3-1 and despite picking up shot-clock violations, the Greek world number 11 fended off a couple of break points for Draper before closing out the opening set.

Draper, 22, regrouped for the second set, his serve this time holding up well, before forcing home a break point opportunity in the 10th game following a double-fault by Tsitsipas to level the match.

The British number one was soon under pressure again as Tsitsipas had three break points in the opening game of the deciding set, but Draper recovered for a crucial hold.

Tsitsipas looked to have taken a decisive break in the ninth game, only to find himself 0-40 down following another call for time violation and a double fault, which saw Draper back on level terms at 5-5.

Draper, currently ranked 28 in the ATP standings, held to put the pressure back on Tsitsipas before converting a superb return to seal another hard-earned victory, 3-6 6-4 7-5.

"In these conditions it is really difficult, the courts are insanely fast, the fastest I think I have ever played in my life," Draper said in his post-match interview, broadcast by Sky Sports.

"It is hard to play good tennis, and at the start, I really struggled. That is just not good enough against these top players.

"In general my grit, my determination and attitude won me the game today, so I am very proud of that."

Draper will have to wait to find out his last-16 opponent, heavy rain ending the day's play before Casper Ruud and Felix Auger-Aliassime were able to take to the court.

Elsewhere, Hubert Hurkacz came through 3-6 7-6 (4) 6-1 against qualifier Yoshihito Nishioka, who was handed a code violation game penalty after hitting balls into the crowd as his frustrations boiled over during the deciding set.

World number seven Andrey Rublev saw off China's Zhizhen Zhang 6-4 6-3 to make the last 16 and third seed Alexander Zverev beat Karen Khachanov 6-3 6-2 while Holger Rune came through 6-3 7-6 (8) against Nuno Borges.

American Ben Shelton delighted the home crowd as he battled to a 6-7 (6) 7-6 (7) 6-3 win over Argentina's Tomas Martin Etcheverry.

Grigor Dimitrov, though, suffered an unexpected defeat to Hungarian Fabian Marozsan, who fought from behind to win 4-6 6-4 6-3.

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