NEW YORK, Sep 3 (Reuters) Serbian teenager Ana Ivanovic was disappointed after being dismissed by Wimbledon champion Venus Williams in the fourth round of the US Open but tried to take positives out of her season.

''Obviously it was very hard for me. It was a little bit disappointing that I lost,'' the 19-year-old Ivanovic said after Williams beat her 6-4 6-2 yesterday.

Ivanovic began the year ranked 14th. After winning in Berlin and Los Angeles, and reaching the French Open finals and semi-finals at Wimbledon, the Serb climbed the list.

''The positive thing is that I'm ranked five, and I still see myself improving in different parts of my game, especially serve,'' she told reporters.

''That's very motivating to know that I can still improve.

There is room for that. Next time I have a better chance.'' Ivanovic, a strong groundstroker who stands 1.83 m tall, said she would focus on her service game.

''It's becoming better, but just not consistent enough,'' she said. ''I have a couple of good serves, but I'm just not getting as many free points as I wish I could get.

''I'm quite tall, so my serve can be one of the most dangerous parts of my game and definitely still needs improvement.'' Ivanovic lost for the fourth time in four matches against Williams.

''Percentage wise I have to beat her sometime. She's a very tough player. It was bad luck for me in the draw, to play her so early here. Just the kind of things you can't control.'' Last year, the furthest Ivanovic advanced in a grand slam was the fourth round at Wimbledon. She reached the second round in her first U.S. Open in 2005 and the third round in 2006.

''Every year here I play one round further,'' Ivanovic said.

''In a couple years' time I might win this.'' Reuters BJR VP0725