British men's No.1 Jack Draper retired from his Japan Open quarterfinal against France's Ugo Humbert on Sunday after struggling with an abdominal issue.
The 22-year-old had lost the first set 7-5 and was 2-1 down in the second before taking a medical timeout to receive treatment on his abdominal area. He attempted to continue before retiring.
The Brit made a dream run to the US Open semifinals this summer where he was eventually beaten in straight sets by world No. 1 Jannik Sinner in a match that lasted just over three hours. Draper vomited three times in the second set as he struggled with the heat and humidity at Flushing Meadows.
Draper had secured his place in Sunday's quarterfinal after a dominant straight-sets win over No. 2 seed Hubert Hurkacz on Friday. It was his third win against a top-10 ranked opponent this season.
Humbert will face Tomas Machac in the semifinal.