MOSCOW - Venus Williams was beaten in the opening round for the second time in 12 tournaments this season, losing 6-4, 2-6, 6-4 to Flavia Pennetta of Italy at the Kremlin Cup on Tuesday.

The Wimbledon champion, who also lost in the first round at Memphis in March, dropped to 1-3 against Pennetta.

"I totally came here because I love winning," the eighth-ranked American said. "I have never won this title, but I just had a day where I could not control my game. She played well."

Svetlana Kuznetsova and Vera Zvonareva, two seeded Russian who have never reached the final of their home event, won their first-round matches.

On the men's side, where Russians have won nine of the last 11 Cups, the winners included two-time defending champion Nikolay Davydenko and Marat Safin, runner-up to Davydenko in 2006.

Pennetta and the sixth-seeded Williams traded breaks in the first set before the Italian broke decisively on her third chance in the ninth game with a lob.

Williams broke twice in the second set, but dropped serve in the first game of the third and never recovered.

"I think the match was very tough," said Pennetta, a two-time winner on tour this year. "Venus is always a tough opponent. Today, I was playing my best tennis. My service was working very well. I am very happy with the match."

Davydenko beat Florent Serra of France 6-1, 7-5, and seventh-seeded Safin struggled past Israeli qualifier Noam Okun 7-6 (5), 3-6, 6-4 to begin his 12th attempt to win the hometown event.

Davydenko, who also won the title in 2004, improved to 16-2 in Moscow.

"I would like to defend my title here, but as usual I'm my worst enemy," he said.

Robby Ginepri of the U.S., beat Jiri Vanek of the Czech Republic 6-3, 6-4 and eighth-seeded Janko Tipsarevic of Serbia held off Russian qualifier Alexandre Kudryavtsev 4-6, 6-3, 7-6 (6).

Former U.S. Open champion Kuznetsova earned a 6-4, 7-5 victory over Li Na of China, who ended Serena Williams' reign as No. 1 last week in Stuttgart.

"Li Na beat many serious opponents this season and to win in two sets, I think, it's not a bad start to the tournament," Kuznetsova said. Ranked No. 7, she has lost all seven of her WTA Tour finals this season.

Seventh-seeded Zvonareva ousted Maria Kirilenko 6-4, 6-4 and Ekaterina Makarova beat Elena Vesnina 7-6 (4), 7-6 (1) in all-Russian matches.

In another men's match, Uzbek qualifier Denis Istomin upset sixth-seeded Michael Llodra 7-6 (2), 6-3 in only his second ATP match.

The 121st-ranked Istomin will face French veteran Fabrice Santoro in the second round.