Sometimes, being No. 1 means you find a way to win with less than your best. Jannik Sinner found that out on Monday in the third round of the Mutua Madrid Open, as he saved a set point and rallied from 5-3 down in the second set for a 6-2, 7-5 win over unseeded Pavel Kotov.

The Australian Open champion, playing as the No. 1 seed at an ATP Masters 1000 event for the first time in his career, was also broken twice in the first set by the upset-minded Russian, but the world No. 72 couldn’t find the consistency needed to truly push the match the distance when he gained the upper hand in the second set. Kotov had previously been 0-5 in 1000-level main draws in his career previously, but defeated Spain’s Albert Ramos-Vinolas and No. 32 seed Jordan Thompson to earn his shot at Sinner.

Sinner has lost just twice to a player ranked outside the Top 50 since the start of the 2023 season. But despite hitting more than twice Kotov’s total of winners, and less unforced errors, the top seed struggled to find his usual crispness due to an existing hip problem.

Twice up a break in the opener, he lost serve straight away afterwards, and he lost three straight games after holding at love to begin the second set.

Sinner was one point away from dropping his first set in Madrid, but navigated through to his first round-of-16 at the event.

But down 5-3, the switch flipped, and Kotov, bidding for his first Top 20 win, blinked after failing to convert a set point in the ninth game.

Sinner navigated all of the further complications presented to him, including an underarm serve by Kotov in the match’s final game, to advance after one hour and 38 minutes. The Italian needed four match points to win, and denied Kotov three chances to push the set to a tiebreak.

“I have been struggling a little bit with my right hip,” Sinner said afterwards in his on-court interview. “We’re trying to find a solution and I don’t think it’s anything serious. Sometimes, I feel it more, like today, and some days are a little bit better.”

Sinner is through to the last 16 in Madrid for the first time in his career, having fell in the third round in 2022. He missed the tournament last year. In the fourth round, Sinner will face No. 16 seed Karen Khachanov, who defeated his compatriot, fellow Italian Flavio Cobolli, in straight sets.