Petra Kvitova goes through ups and downs

Petra Kvitova of the Czech Republic comments on her play at the WTA Championships in Istanbul, Turkey, which runs from Oct 22 until Oct 27:

I feel really good (to win the first match against Agnieszka Radwanska of Poland). I mean, the first match is always tough in the Championships, and in other tournaments, too.

I was nervous before the match because I recalled last year,when I lost to her (in) the first match of the Championships, so I'm really glad that I won today.

I finished quite late today, and I'm glad that I have tomorrow off so that I can practice a bit, rest in the afternoon and have more energy for the next match.

Serena is a big favorite of our group, and she played well today, starting pretty aggressively. For me, it's a big challenge to face her, so I'm looking forward to the match.

I would give a "6" for my performance this year because it has been full of ups and downs I had a few difficult times this season; it is always tough mentally. I lost my confidence a little bit. It was tough, but I tried to be as positive as I could be. I worked very hard, and I have great people who always trust me.

As for next year, I will try to return to the top five. I have a new fitness coach, so I am looking forward to the preparation .

Fans in Istanbul are incredible. I remember in 2011 when I was here for the first time, people didn't come a lot. It was full attendance in the finals in 2011, and last year it was full for every match. I think Turkish people like to watch tennis.

One of this year's great memories was that I took a photo with Li Na before the draw ceremony. We are close friends. She is nice, and we always have lots of fun. We understand each other well.

I know that next year a new tournament will be in Wuhan, which is Li Na's hometown. I think there will be huge support for Li Na, so it is going to be tough to play her there.

Xiexie!