Petra Kvitova encouraged that she can still compete at a high level

Petra Kvitova has gained confidence from her run at the US Open, her best showing at a Grand Slam since her return to tour.

The Czech recorded a fourth-round win against Garbine Muguruza, who was coming off a title at Wimbledon, and fell to Venus Williams in a third-set tiebreak in another high-quality encounter in the quarterfinals.

"I'm glad that I am still able to compete on the high level against the top players, which I hope will give me some confidence for hard work again, to continue to play well, to know that it's still there somewhere," she said.

Kvitova's left hand was badly injured by an intruder in a knife attack during the offseason, putting her career in doubt.

She returned at the French Open, and then won the title in Birmingham, but had not played any Top 10 opponents until Flushing Meadows.

"I didn't really think that I can come so far. Was great to win in Birmingham, but I think was pretty early that I put a little bit pressure on me, and I just wanted to play better and better, which I wasn't pretty ready for that. I'm just glad that I could show it here," she said.

The run has also left her eager for the next part of the season.

"It's a pretty long trip in Asia, but I didn't play for five, six months," said Kvitova. "I'm really looking forward to be there standing on the court again."

Kvitova is No. 14 in the rankings.