Defending champion Carlos Alcaraz and world No.1 Jannik Sinner are one match away from another high-stakes meeting in the Wimbledon semi-finals.

Both men reached the quarter-finals on Sunday as Alcaraz held off an attempted comeback by Ugo Humbert to win 6-3, 6-4, 1-6, 7-5 on Centre Court. Sinner then beat Ben Shelton 6-2, 6-4, 7-6 (9) on No. 1 Court after saving four set points in the third set.

Alcaraz beat Sinner in five sets in the French Open semi-finals in June en route to his first title at Roland Garros and the two would meet again in the last four if they win their next matches.

Both players came up with some spectacular shots when it mattered on Sunday.

Alcaraz’s match against Humbert had seemed all but over when the Spaniard clinched the second set by chasing down several seemingly out-of-reach shots on set point, even falling over after hitting one forehand and quickly getting back up to get to the next ball.

Asked to describe his play on that point, Alcaraz just said: “Unbelievable, I guess.”

Humbert nearly staged a surprising comeback and threatened to take the match into a fifth set when he held three straight break points for a 5-3 lead in the fourth. But Alcaraz came back to win that game with the help of a couple of aces, then broke for a 6-5 lead by hitting a deep forehand winner.

He set up match point with one of his delicate forehand drop shots and converted it with a service winner.

Sinner had to come from 4-1 down in the third set and held for 5-5 after wrapping his racket behind his back and hitting the ball between his legs to get it over the net, then followed it up with a forehand passing shot to clinch the game.

Sinner then saved one set point at 6-5 and three more in the tie-breaker before converting his second match point when the hard-serving Shelton double-faulted.

Shelton was trying to reach his first Wimbledon quarter-final but was coming off three straight five-set wins, including one over Denis Shapovalov that finished on Saturday.

Sinner is into the last eight for the third year in a row, having lost to Novak Djokovic in last year’s semi-finals.

Daniil Medvedev advanced when Grigor Dimitrov retired while trailing 3-5 in the first set.

A first for the Italian

French Open runner-up Jasmine Paolini reached her first Wimbledon quarter final when Madison Keys had to retire with a leg injury at 5-5 in the third set of their fourth-round match.

Keys had served for the match at 5-2 in the last set but then started limping more and more and needed a medical timeout to get her left leg worked on after Paolini made it 5-4.

She had her left thigh taped as she served for the match for a second time but was broken again — double-faulting on break point — and was in tears by the end of that game, with her movement clearly restricted.

Keys tried to play on but the American finally went to the net to tell the chair umpire on No. 1 Court that she was retiring after Paolini hit an ace for 15-15 in the final game.

The Italian had won the first set 6-3, before Keys won the second 7-6 (6).

Keys had been two points from the win when the score was deuce at 5-2 in the third.

“I’m so sorry for her. To end the match like this, it’s bad,” Paolini said in her on-court interview.

“A lot of ups and downs. I’m feeling a little bit happy, but also sad for her. It’s not easy to win like that.”

Paolini is the fifth Italian woman to reach the Wimbledon quarter-finals in the professional era, and will try to become the first to make the semi-finals.

Croatia’s Donna Vekic reached the Wimbledon quarter-finals for the first time with a rain-interrupted three-set win over Spain’s Paula Badosa.

The 28-year-old world No. 37 triumphed 6-2, 1-6, 6-4 and goes on to face New Zealand qualifier Lulu Sun who defeated Britain’s Emma Raducanu 6-2, 5-7, 6-2.