Second-seeded Reilly Opelka has advanced to the quarter-finals of the inaugural Dallas Open with a straight-sets win over Cedrik-Marcel Stebe on Thursday night.

Opelka, a two-time ATP Tour winner ranked 23rd in the world, won 7-6 (7-3) 7-6 (10-8) to set up a clash with fifth-ranked Frenchman Adrian Mannarino, who beat Yoshihito Nishioka, 6-3 6-1 in just over an hour.

Mannarino has reached back-to-back quarter-finals for the first time since October 2020.

“I played well in the big points,” Opelka said.

“I stayed in the tiebreakers, competed hard, it could have easily gone to a third set.”

Fourth-seeded Jenson Brooksby, playing with a career-best No.54 world ranking and seeded in an ATP Tour event for the first time in his career, also advanced to the last eight with a 6-3 3-6 6-3 win over Italian Andreas Seppi.

Brooksby will face Australia’s Jordan Thompson in the quarters on Friday.

The 21-year-old American who reached fourth round as a wild card in the 2021 US Open, has yet to win an ATP Tour title despite a breakout 2021 that included 49 professional victories and three ATP Challenger titles.

“It felt pretty good,” Brooksby said.

“A little nervous, being in my first match of the year. It will always be a tough feeling losing early, but I competed well.”

Canadian qualifier Vasek Posposil continued his strong start to 2022, beating Austrian Jurji Rodionov, 6-7 (7-3) 7-6 (8-6) 6-2. The 31-year-old with a far more successful doubles career, is seeking his first singles title since turning pro 15 years ago.