Radwanska of Poland kisses the trophy after winning her final match against Zvonareva of Russia at a WTA tennis event in Carlsbad
Agnieszka Radwanska of Poland kisses the trophy after winning her final match against Vera Zvonareva of Russia at a WTA tennis event in Carlsbad, California August 7, 2011. Reuters

Agnieszka Radwanska won the biggest hard court title of her career when she upset world number three Vera Zvonareva of Russia 6-3 6-4 to win the San Diego Open on Sunday.

The third-seeded Radwanska adeptly mixed up the pace and direction of her ground strokes, took over the net and showed no evidence that her heavily taped shoulder was bothering her.

"Playing the Russian(s) in the finals is always tough," Radwanska told reporters. "I played very well today. I'm very happy with my performance. Winning a tournament with a lot of great matches against top players, it's always very special."

Radwanska began the match near perfectly and never let her foot off the pedal. She broke Zvonareva to 3-1 with a forehand winner down the line and easily held in her next three service games before she won the first set with a leaping backhand winner.

Zvonareva, who had played late on Saturday to hold off Ana Ivanovic, tried to push herself forward, but her usually searing ground strokes were a little off and Radwanska won most of their extended rallies.

"I think I was playing the right shots," said Zvonareva, who hit 25 winners but committed 28 unforced errors. "I was maybe just a little slow.

"My footwork wasn't perfect, and that's why I had a few mistakes. Of course against Agnieszka, when she's playing well, if you have those mistakes, it's tough to win."

Radwanska broke the Russian to take a 3-1 lead in the second set when Zvonareva erred on backhand, and then fought off her only break points of the match to hold to 4-2.

In the final game Zvonareva tripped and fell trying to chase down a forehand but was unhurt before Radwanska won the title when Zvonareva hit a forehand long.

"Everything was working," Radwanska said. I was playing very well, even when I had a really tough two matches in the quarters and semi-finals. I really wanted to win this tournament. So I was really focused from the beginning."

It was the fifth title of the 22-year-old's career, but was her first WTA premier title on hard courts, with her only previous premier title on grass at Eastbourne in 2008.

The victory ensures Radwanska will rise to 12th in the WTA rankings when they are released on Monday and gives her a major confidence boost heading into the U.S. Open.

"I was pretty close (to reaching a grand slam semi-final) a few times, but I was always against top players and it was always close," she said.

"I cannot say I was playing bad before, but I couldn't close those tight matches.

"A lot of good matches, but it was always something wrong with me in the end that I couldn't win.

"But I think I can do it, and if I play like that (like Sunday), for sure.

"So I'm just going to keep going and hope I can show some good tennis especially at the U.S. Open."