Top-seed Frances Tiafoe has ended Australian Jason Kubler's run at the rain-interrupted Houston Open in the quarter-finals as both men played two matches in a day.
Two-and-a-half hours after a second-round 6-2 6-4 victory against fellow American Steve Johnson, Tiafoe returned to court and ousted Kubler 6-4 6-4 to reach the semi-finals of the claycourt event in Texas on Saturday.
Siixth seed Kubler had beaten Colombia's Daniel Elahi Galan 6-2 6-3 earlier in the day.
"I haven't played two matches in one day in a long time," world No.15 Tiafoe said. "I thought it was unbelievable how I was able to come out here and play so well.
"The ball was going much (faster), it was much warmer (than earlier), I was sweating a lot more.
"(Kubler) has been playing well, he's played a lot lately, so I knew he was going to come after me. It was a good match."
Tiafoe won 28 of 31 points off his first delivery against Kulber and will next meet Houston-born Gijs Brouwer in the last four.
Dutchman Brouwer completed a 6-4 7-6 (7-4) win over fourth seed John Isner on Saturday then continued his strong run by upsetting fifth seed J.J. Wolf 6-3 6-4 to reach his first ATP semi-final.
After rain cancelled much of play the past three days, the Houston Open semi-finals and championship match will be held Sunday.