World number one Novak Djokovic has set up a meeting with Olympic champion Alexander Zverev in the US Open semi-finals after coming from behind to beat Italy's Matteo Berrettini 5-7, 6-2, 6-2, 6-3 on Wednesday night.
Berrettini started the rematch of the Wimbledon final well, going a break up with his powerful serve proving fruitful.
After the world number six squandered three break points, Djokovic fired a forehand wide to hand the Italian the opening set after 77 minutes.
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The contest became far more routine for the world number one en route to his 26th consecutive victory at a major as the Serb wrapped up the match in three hours and 26 minutes.
Djokovic's bid for the Calendar Grand Slam continues against Zverev, who beat Lloyd Harris in straight sets earlier in the day.
The German defeated Djokovic at the Tokyo 2020 semi-finals to deny him the golden slam and the Serb is fully aware he has a tough match on his hands.
Djokovic said post-match: "He's in tremendous form, he's been winning a lot. He has comfortably moved to the semi-finals here.
"I know his game well, we played in Tokyo. He's one of the best players in the world, but the bigger the challenge the more glory in overcoming it."
After Zverev beat Harris, his 16th win in a row, he said: "I feel like I was the first player to beat [Djokovic] in a very big match this year.
"I mean, it's the biggest tournament in the world. It's the Olympics. Winning there against the world number one, especially as I was down a set and a break, being kind of out of the match, then coming back, it was different than the other matches. The emotions were different.
"This year it seems like nobody can beat him in a big match; nobody can beat him at the Grand Slams."
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