Serena Williams (search) earned a bittersweet Wimbledon title Saturday by beating her ailing sister.

With Venus Williams (search) battling an abdominal strain she aggravated in the semifinals, Serena won 4-6, 6-4, 6-2, earning her sixth Grand Slam (search) championship and her second in a row at Wimbledon.

For the first set and a half, Venus appeared largely uninhibited by the injury, which has bothered her off and on for two months. She chased down shots in the corners, smacked crosscourt winners and hit her serve at up to 110 mph.

But the velocity of her serves gradually fell off, and as she hit one early in the third set, she clutched her stomach and grimaced. She lost the point and game to fall behind 1-0, then called for a trainer and left the court to have the tape around her stomach adjusted.

She returned seven minutes later to a big ovation, and her first shot was a forehand return for a winner. But her next four returns were errant, putting Serena ahead 2-0.

Venus twice held serve to stay in the third set. But she double faulted, hunching over in pain on her follow through, to fall behind 5-2, and Serena served out the match.

With the victory, however hollow, top-ranked Serena Williams has won five of the past six major titles. She has beaten her sister six times in a row, with the past five wins in major finals, including two at Wimbledon.

Venus has won four major titles, but none since beating Serena in the first all-Williams Grand Slam final at the 2001 U.S. Open. The family has won four consecutive titles at Wimbledon — Venus was the champion in 2000-01.

The men's final Sunday will match No. 4-seeded Roger Federer against unseeded Mark Philippoussis, with both playing for their first Grand Slam title.

Venus Williams didn't practice Friday, and two hours before the final she warmed up for only 10 minutes before limping off the court to the locker room.

But Venus had pledged "to at least show up," and she did. A bandage around her stomach was visible under her corset dress, and she also had her upper left leg wrapped.