Tennis-Kvitova overcomes tough start in straight-sets second round win

She got back on track in the second set to break Kozlova's serve in the first game before firing off consecutive aces and a pair of winners en route to a 2-0 lead. A relieved Kvitova wrapped up victory with a powerful serve that a beleaguered Kozlova was unable to return.

Petra Kvitova overcame a rocky start to defeat Kateryna Kozlova 7-6(3) 6-2 in the second-round of the U.S. Open on Wednesday. Sixth seed Kvitova was off her game early on, committing 20 unforced errors during the first set - twice as many as her Ukrainian opponent - as she struggled with her serve.

The twice Wimbledon champion committed a fifth double fault to hand Kozlova a break point and a 3-2 lead but recovered to save set point at 5-4 and eventually took the set on a tiebreak. She got back on track in the second set to break Kozlova's serve in the first game before firing off consecutive aces and a pair of winners en route to a 2-0 lead.

A relieved Kvitova wrapped up victory with a powerful serve that a beleaguered Kozlova was unable to return. "I couldn't move well, I couldn't swing as I wanted," the 30-year-old Czech said. "I'm really happy that I found the way. I really had to fight."