Q. What were the keys to the match today?
PETRA KVITOVA: It was kind of weird match, I think. I mean, from the beginning I was facing a lot of breakpoints on my serve. I don't know how, but it doesn't matter. I was kind of able to keep the serve still.
And then I was just waiting for some chance, which came twice. She double-fault. So she kind of helped me for making the set in both sets.
She served very well, for sure. I think she didn't really miss that much. So she really made me to play a lot. It was really good match and very tough.
Q. What are your thoughts on Flavia and the challenge of facing her?
PETRA KVITOVA: Flavia is a good girl, so I'm looking forward for the match. It's a long time we played each other, I think. I think she's on fire. She's playing well here. She beat Sam in two sets. So I think she really has to feel well.
It's quarterfinals, so I don't really think that someone easy to beat there. I'm looking forward. It's my first time in quarters. I will enjoy that for sure.
Q. Two players that have been to the quarterfinals a lot are the Williams sisters. When they're playing each other, what's it like from your perspective?
PETRA KVITOVA: I don't care. I mean, it's a quarterfinal match. Of course it's weird that sisters are playing together, like against each other. It's not the first time for them and maybe not the last time. They should be used to it already.
Q. Do you remember watching any of their matches? If so, what was going through your mind as you saw this unusual matchup?
PETRA KVITOVA: I think I saw maybe one kind of not all the match. But it was final of Wimbledon, I think. But it's kind of long time ago and I'm not really remember.
Yeah, I think you can be friends, maybe sisters off the court and still maybe when you step on the court, maybe the emotions are not show up as normally you do. But still you want to win and you have to fight.
Yeah, it's weird. That's how it is.
Q. As somebody that has been at the top of the game, how would you assess Jo Konta's game and what kind of potential do you think she has?
PETRA KVITOVA: You know, I think 15 or 16 straight matches she has. I think it's great, for sure. Not really everyone can have it. So, I mean, that's saying a lot about her, about her game right now.
I know it's still kind of from the challengers, but still the confident really growed. She really have had great tournament. She beat Muguruza, she beat Petkovic. It's not really easy players.
I think if she's going to keep that level which she showed today on the center court, as well, she can be really good player.
Q. You said she served very well today. Was there anything else about her game that surprised you?
PETRA KVITOVA: Yeah, I knew what I should expect. On the other side, I think she moved very well. She catch a lot of balls. Sometimes I maybe should go for the volleys little bit more than I did.
But I think she really didn't miss that much. I mean, I was helping with the serve sometimes in the important points, which was really good for me. But she was really trying, you know, to push me little bit. Her backhand was very good. I was trying little bit to play to the forehand. But it wasn't easy either.
I think she's kind of consistent player.
Q. If somebody had told you you'd make the quarterfinals at the US Open this year about 10 days ago, what would you have thought?
PETRA KVITOVA: I think he is mad. But, yeah, it's weird. I'm surprised, as well, how everything went. I mean, I really didn't expect that.
I mean, after Wimbledon, I mean, I was really trying -- not trying, but I was kind of setting the goals that I really wanted to do well in the US Open, that I really wanted to break this kind of results here and still qualify to Singapore.
I'm not really thinking about that, but it's just happening right now. It's a great thing to happen. I'm really, you know, happy. I was waiting for this time to break the quarterfinals here many years. I'm really glad that finally it's here.
Q. What feels different this year for you than in years past that you think made a difference?
PETRA KVITOVA: I think the different is that I'm probably feeling the best which I ever feeled here. Maybe it's, of course, connected with kind of my health which I'm not practicing that much, I'm kind of little bit quiet, not really doing these normal kind of things, not really expectation from myself. I didn't want to put that pressure that much on me.
I don't know. I think the last week in New Haven helped me a lot, which was great. I'm still able to, you know, show kind of the game here. That's it probably.
Q. In what ways do you think you're playing better?
PETRA KVITOVA: In which ways? I think the serve is working quite okay. I mean, for sure. And I think that I have kind of game plan, which means that if I need to be more patient, I am able to be. If I have to really attack the balls more, I can do that.
I think it's kind of probably the mental thing as well, that I can really kind of play with the plans.
Q. You mentioned the word 'quiet' a couple seconds ago. You played Ashe tonight, which is certainly not quiet. How much do you enjoy it?
PETRA KVITOVA: Actually I'm starting to like it. It's good. It's not like Wimbledon, of course. It's still lot of noise up there. I think when they going to make the roof, it's maybe more silence there -- no, noisy, sorry.
I think it's kind of a US Open. It should be like that. I think it's kind of energy city. The people having big, big-time, showtime on the center court. I think it should be like that.
Actually, I'm not really thinking about that because I'm focusing on me, my game, everything. So for me is not really bothering me.
Q. Sometimes on match point, it's so loud. Did you notice that?
PETRA KVITOVA: I did. I did. And the goosebumps weren't there.
It was very nice. Unfortunately I lost the two points afterwards. But they get loud again in the 40-30. I was really happy I made the last point.
Q. How much less are you practicing now than you were before Wimbledon? Can you say in hours or numbers or something like that?
PETRA KVITOVA: It's probably a question for my coaches. I have not everything writing down. But before Wimbledon, actually I got sick in Eastbourne, so I didn't practice that much, as well.
Really, I mean, the number of hours is very low.
Q. Does it feel like half? More than half?
PETRA KVITOVA: Yeah, probably. I mean, when I find out I have mono, I was really cutting the hours down. I was practicing only once a day, maybe hour, and in the afternoon have 30 minutes of fitness. I really didn't practice that much.
Yeah, it's really kind of half, let's say.
Q. Seems like your expectations have been pretty low coming into this tournament because you were sick. Now that you're in the quarterfinals, is that still the case?
PETRA KVITOVA: As I said in my last press conference, I mean, every win which I have is a bonus to have for me. I'm very happy that the bonuses are still growing.
But I know that Flavia is tough. She really knows game well. I know I have a chance. But still, I mean, the expectation... Of course, I want to do well. I'm not saying I'm not. But it's just more relaxed probably. Not really expectation to be in the semifinal right now. But it's still long time to go.