Djokovic defied a calf injury suffered in the first set to win 7-6 (12/10), 3-6, 6-3, 6-7 (4/7), 7-6 (10/4) in a Centre Court classic lasting five hours and 15 minutes.

The indefatigable 39-year-old will meet world number one Sinner on Friday for a place in the final.

While Sinner beat German veteran Jan-Lennard Struff in straight sets on Tuesday, Djokovic had to dig much deeper before he subdued Canadian third seed Auger-Aliassime in one of the all-time gutsy Wimbledon performances.

The question now is whether the Serb will have anything left in the tank to beat Sinner.

Asked how he saw off Auger-Aliassime, Djokovic said: "With racquet and a lot of heart. I have management of the nerves and the extreme tension you feel in these kind of matches.

"Towards the end, it was really anyone's game. What can I say, these are the kind of moments that I still play tennis for, for sure.

"I was telling the kids to go to sleep, I'm glad they stayed because it was one of the best matches I was part of on this court in my career."

Djokovic has advanced to a record-extending 15th Wimbledon semi-final and 55th at the Grand Slams.

He is into the Wimbledon last four for an eighth consecutive time, setting a new record ahead of Roger Federer for the longest streak of men's singles semi-final appearances at the All England Club.

Djokovic is only the second player in the Open era to reach the men's semi-finals at Wimbledon aged 39 or older after Ken Rosewall in 1974.

Sinner wasn't at his best against Struff, but his booming serve kept the world number 74 at bay as he reached his 10th Grand Slam semi-final and third at Wimbledon.

"It was a huge test today. I felt comfortable on the physical side, a good step forwards," the Italian said.

- 'I was very nervous' -

In the women's tournament, Coco Gauff and Karolina Muchova reached their first Wimbledon semi-finals.

The all-American encounter on Centre Court went Gauff's way as the seventh seed beat Jessica Pegula 4-6, 6-3, 6-3.

Gauff a two-time major champion was appearing in the last eight at the All England Club for the first time.

Seven years after she became the youngest player to reach the Wimbledon main draw aged 15 and then stunned Venus Williams on her debut, Gauff is two wins away from an even more impressive feat at the All England Club.

The 22-year-old is into the semi-finals of a Grand Slam for the first time since winning her most recent major at the French Open last year.

She is the youngest player to appear in all four Grand Slam semi-finals since Maria Sharapova in 2007.

"Considering I hadn't won a match in two years on grass before this tournament, I'm really happy with how I played today," Gauff said.

In the last four, Gauff faces Czech 10th seed Muchova, who beat Japanese star Naomi Osaka 7-6 (7/4), 6-4.

Muchova had never been past the first round in her four previous visits to Wimbledon, but she won the grass-court tournament at Bad Homburg in June.

"Oh my god, I was very nervous! I know you can't lose focus because if you give her a little chance, she takes it," Muchova said.

The 29-year-old lost her only Grand Slam final appearance against Iga Swiatek at the 2023 French Open.

French Open champion Alexander Zverev finished off his delayed last-16 tie against Jiri Lehecka, winning 6-4, 7-5, 3-6, 7-6 (8/6) to book a quarter-final clash with American sixth seed Taylor Fritz.

Zverev had been leading by two sets when the match was halted by the 2200 GMT curfew on Monday.

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