TOKYO (AP)Taylor Fritz advanced to the Japan Open semifinals after Nick Kyrgios withdrew because of a left knee injury on Friday.

Fritz, who spent a week in quarantine after testing testing positive for COVID-19 in Seoul last week, will next face Denis Shapovalov. The seventh-seeded Canadian defeated Borna Coric 6-4, 6-3.

Frances Tiafoe reached the semifinals by beating Miomir Kecmanovic 6-0, 6-4. Tiafoe, who has not dropped a set in Tokyo, will be making his fourth semifinal appearance this season.

”I was moving really well. I hit the ball well from the back of the court,” Tifoe said. ”I made it really tough for Miomir today. He played some great tennis. I was lucky enough to get it done in straight sets. Performances like this are big.”

Tiafoe will next take on Kwon Soon-woo. The South Korean defeated Pedro Martinez 6-3, 6-0.

Kyrgios’ knee injury also forced him to withdraw from the doubles semifinals, where he and partner Thanasi Kokkinakis were scheduled to play Mackenzie McDonald and Marcelo Melo.

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