NEW YORK (Reuters) - Czech Petra Kvitova struggled with unforced errors but still had enough weapons to defeat American Jessica Pegula 6-4 6-3 on Friday to advance to the fourth round of the U.S. Open.
The two-times Wimbledon champion had 28 unforced errors and five double faults but moved up a gear when it mattered to win her first career meeting with baseline battler Pegula.
Sixth seed Kvitova broke the world No. 63 twice in each set and completed the win when Pegula sent a return wide.
"I'm definitely happy that I'm through the first week. Few weeks ago I didn't have idea that really the U.S. Open will take place. For me (it) was a miracle that it's really happening.
"I know that if I didn't come maybe one day I (was) going to regret that I didn't come."
Pegula, who reached the last eight of the Western & Southern Open warm-up event, matched Kvitova shot for shot from the baseline early on, forcing the Czech left-hander to save two breakpoints in the fifth game.
Kvitova decided to mix things up by advancing to the net more often and after a trade of breaks she managed to take the opener with a second break of serve.
Kvitova lost concentration at the start of the second set and as her errors mounted she let loose several screams to get some positive energy back into her game.
After falling behind 2-0 she won the next three games to bring the set back on serve. Pegula held to make it 3-3 before Kvitova went on another three-game run to finish the match.
"Second set I was down. It was really a big fight those two or three games which I really had to fight very hard. That probably was the turning point," Kvitova said.
"I tried to go little bit more for the volleys I would say because she really played great from the baseline."
The U.S. Open is the only Grand Slam event where Kvitova has failed to reach the semi-finals and next up for her will be another American in Shelby Rogers (NYSE:ROG), who earlier advanced with a 6-2 6-4 win against compatriot Madison Brengle.