Kvitova fights back from knife attack to shine through

NEW YORK — Battling back after a home-invasion knife attack last December that jeopardized her career, two-time Wimbledon winner Petra Kvitova matched her top US Open performance Sunday by reaching the quarterfinals.

The 13th-seeded Czech left-hander ousted Spanish third seed and reigning Wimbledon champion Garbine Muguruza 7-6 (7/3), 6-3 to book a Tuesday last-eight date with US ninth seed and seven-time Grand Slam winner Venus Williams.

Kvitova, who also reached the 2015 quarterfinals, is playing only her eighth event of the year after left hand surgery following a break-in assault last December that is still under investigation by Czech police.

"Especially after everything that happened, I do feel little bit pumped," Kvitova said. "I don't really have the best ranking, but on the other hand I know I can play well, which I showed today.

"I worked hard to come back and be here. It means a lot."

Kvitova, whose All England crowns came in 2011 and 2014, said after her victory in Arthur Ashe Stadium that her journey back from the attack has been a difficult climb.

"It was a tough time. All five months were very tough. It was just a journey I didn't know how it would end.

"If it ends here on the big stage it's a happy end."

Kvitova has a greater appreciation for the tour lifestyle after an injury that put her career at risk.

"I'm very grateful that I can be part of it again," Kvitova said. "The life is still a little bit strange, but it's getting better. It's much more easier for me to feel more normal than before."

She said her hand is not yet fully healed but has come far enough for her to produce formidable performances.

"I think still my hand is not 100 percent ready, so I do feel I have space to improve," Kvitova said. "I'm still working on the strength. I'm really not thinking about it when I'm playing much. I'm just taking how it is.

"Movement is still not great, but for the grip of the tennis racquet it so far is OK."