Carlos Alcaraz rides his luck through to Japan Open SF following retirement

Shapovalov was up 7-6(3), 2-1 when he was forced to retire hurt after 82 minutes. The Canadian appeared to suffer an injury at the beginning of the second set when he stretched for a forehand and pulled his hip. He took an off-court medical timeout after the opening game, but then was unable to continue.

Alcaraz's serve was cause for concern. The Spaniard dropped serve three times in the opening set as Shapovalov took control and looked to be well in charge of the match.

"It was a little bit frustrating with my serve,"Alcaraz told the press after the match.

"I couldn't find a good way of serving: I was struggling almost every game on serve. But I'm just happy with the way I came back after every break. It was a great first set: Great points, great rallies.

"It's a shame that he had to pull out. Going through to a semifinal like this is not the way I wanted, but sometimes sports are tough. You have to accept it. Hopefully he's going to be able to play in Shanghai healthy."

Alcaraz now faces fellow countryman Jaume Munar in the final four after Munar eased past Kyrian Jacquet 6-4, 6-2 in his quarterfinal.

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