The American player saved a break point at 4-4 in the first set, won the tiebreaker, and saved two more in the second set before wrapping up the win.
“I enjoyed it, being on grass. It’s one of my favorite surfaces and I love being here, playing on grass. So let’s see how it goes,” said Tiafoe, whose speed helped his return game against Lehecka.
Tiafoe, 25, next plays sixth-seeded Lorenzo Musetti in the quarterfinals. The Italian player defeated Gregoire Barrere 6-3, 6-3 in their second-round match. Musetti saved all seven break points he faced.
Also, in a meeting of two big-serving players, former Wimbledon semifinalist Hubert Hurkacz won 4-6, 7-6 (5), 7-6 (5) against qualifier Yosuke Watanuki after feeling unwell during the match. Hurkacz is known as one of the tour’s top servers but had only 21 aces to 27 for Watanuki.
It was the first time in the Polish player’s career that he won his opening match of the grass-court season and it was also Hurkacz’ first win in three appearances in Stuttgart.
“Yosuke played really well, it was a super tough battle and just really happy to get through this one,” Hurkacz said. “He was serving really well and also playing from the baseline really aggressive. It’s grass-court tennis.”
Frances Tiafoe, Lorenzo Musetti move on to Stuttgart quarterfinals