Two-time defending champion John Isner beat Radek Stepanek 7-6 (3), 7-6 (7) on Thursday night in his opening match in the Atlanta Open.
The top-seeded Isner has reached the final four of the last five years, winning the last two after losing to Mardy Fish in 2010 and 2011. Isner is 12-1 in tiebreakers in Atlanta since 2012.
Isner’s booming serve was potent, with the 6-foot-10 former University of Georgia player ripping 33 aces to three for Stepanek. Yet the world’s No. 19-ranked player was on the ropes a couple times against the 144th-ranked Stepanek in the final match of a day that saw three seeded players drop out.
The first set remained on serve before Stepanek, a 36-year-old, 20-year pro from the Czech Republic, hit his first ace to open the tiebreaker. Isner had 14 aces by that point.
Stepanek broke Isner in the middle of the second set to lead 3-2, and quickly won on serve to go up 4-2. Isner, though, then held serve and broke back in a game where he saved a long deep ball by popping it high in the sky to set up an eventual passing shot that surprised Stepanek.
Earlier, Ukrainian qualifier Denis Kudla upset third-seeded Jack Sock 7-6 (6), 6-3, and No. 6 Steve Johnson and No. 8 Benjamin Becker also tumbled out.
Sock, an American ranked 35th, battled in the first set before falling quickly in the second when his service game all but abandoned him as high humidity and temperatures in the mid—90s wore him out.
In the second set, Kudla won 7 of 14 points on Sock’s first serve was 5 of 12 on second serves while breaking the American’s service game twice. Sock entered the match 17—8 in ATP matches this season.
The 94th-ranked Kudla reached the round of 16 at Wimbledon a month ago. He said that having played his way through qualifying probably helped.
“I’m just really happy with my performance in the heat knowing it’s tough to try to come back when it’s that hot,” Kudla said. “I’ve been in the heat now for four days. I’m glad I was able to take advantage of the opportunity knowing it was (Sock’s) first match and he had no rhythm.”
Israel’s Dudi Sela, who fell in the 2014 final to Isner, beat Becker, from Germany, 7-5, 6-3, and Ricardis Berankis of Lithuania rolled past Johnson 6-4, 6-2.
Isner will face Berankis on Friday in the quarterfinals.
