Frances Tiafoe admitted he almost gave up hope after losing a sloppy first set, but lifted his game on Friday to complete a 6-7 (6), 7-6(4), 6-2 quarter-final defeat of Lorenzo Musetti at the ATP Boss event in Stuttgart.
The American is into the first grass-court semi-final of his career after overcoming his Italian opponent in two and three-quarter-hours.
He has twice reached the quarter-finals on the surface at Queen’s club, London.
The third seed twice served for the opener leading 5-3, and 6-5, but was ambushed in the tiebreaker as Musetti took the early lead at the Weissenhof club.
“That was something,” the winner said. “I was really pissed off after losing that first set.
“You could tell by my body language. In the second I thought about just letting it go, but I’m glad I stayed in and competed.
“It ended up being a good day at the office.”
Tiafoe, who admitted he’s “not much of a morning person,” managed to adapt to a breezy afternoon.
“I’m happy with how I played, I had to clean it up after the first set, you can’t serve twice for a set like that.”
