MELBOURNE, Australia -- Venus Williams, supreme at Wimbledon and at Flushing Meadows, stumbled at the Australian Open.

Monica Seles snapped Williams' 24-match winning streak and her bid for a third consecutive Grand Slam title with a 6-7 (4), 6-2, 6-3 quarterfinal upset Tuesday and moved into the Australian Open semifinals against Martina Hingis.

	After taking care of Italy's Adriana Serra Zanetti, right, Martina Hingis figures to have a tougher test in the semifinals.

Seles lost her previous six matches against Williams, who has won the last two U.S. Opens and the previous two Wimbledon titles.

The second-seeded Williams injured her hamstring in the first set and limped for the rest of the match. She'd gone into the quarterfinal with an injured left knee.

Williams reached the semifinals at Melbourne Park last year, when she had the worst loss of her pro career in a 6-1, 6-1 defeat to Hingis. In her previous trips to Melbourne Park, she'd never gone beyond the quarterfinals.

Seles, seeded eighth, has won four Australian Opens, but the last one was six years ago. Hingis is a three-time Australian Open champion, but has not won since 1999, her last title in a major tournament.

Williams won the first set in a tiebreaker despite her injury.

"I had pain in the hamstring area -- I wasn't quite sure what was going on," Williams said. "It hasn't been the best tournament for me health-wise."

Seles won the first eight points and led 2-0 before Williams broke back and held to put the first set back on serve.

Williams injured her hamstring chasing a wide Seles' forehand on the last point of the eighth game and needed a medical timeout and treatment inside the player's tunnel to have the top of her right thigh strapped.

Seles dominated the second set, with her two-fisted forehand and backhand groundstrokes regularly producing winners, and she evened the match at a set apiece in 33 minutes as Williams' error rate increased.

In the third set, Seles broke to lead 3-2 when Williams' wild backhand went long.

At 4-3, Seles gave her younger rival three break points but saved them all for a 5-3 lead, finishing with a backhand winner down the line.

Serving to stay in the match, Williams faced two match points and surrendered on the second when she netted a forehand.

"It was such a tough match, really weird circumstances for both of us," said Seles, who complained of a sore throat and fever going into the match. "We were both fighting a lot of problems within ourselves.

"Venus is such a great champion, I just got lucky there on a couple of points at the end."

The only other time they'd gone head-to-head outside of the United States was at the Sydney Olympics in 2000, when Williams got a three-set win in a semifinal en route to a gold medal.

Williams finished with 49 unforced errors and 10 double faults, almost twice those of Seles, who had 25 unforced errors and five double faults.

"More than anything (Seles) had the gameplan today," Williams said. "Who knows, maybe she'll take the whole Slam home -- that would be an exciting story. She deserves it."

Williams said she'd get some medical advice before deciding where to play next. Although she's now targeting the French Open "to end my nightmare there." She's never gone beyond the quarterfinals at Roland Garros.

Hingis has reached the final at Melbourne Park every year since 1997, when she picked up the first of her three consecutive titles. She was runner-up to Lindsay Davenport in 2000 and again to Jennifer Capriati last year.

"Martina is a very tough player, she's playing some of her best tennis. It's going to be a tough battle, we always play tough ones," Seles said.

In her 6-2, 6-3 win Tuesday over Adriana Serra Zanetti, Hingis looked composed and confident even though it was her hardest match so far. She only conceded nine games in her previous four matches.

Serena Williams, the 1999 U.S. Open winner, withdrew before her first-round match here due to an ankle injury she picked up the previous week in Sydney. Serena and Hingis had been drawn to meet in a quarterfinal rematch.

"I had to face Serena in the quarterfinals here at this point (last year), but it's kind of nice having someone you don't know that well," Hingis said of Serra Zanetti. "It's nice to get through it easier than last year."

Her road to the semifinals this year hasn't been taxing. So far, she's had wins over Virginie Razzano (6-2, 6-2), Greta Arn (6-1, 6-2), Barbara Rittner (6-1, 6-0), and Amanda Coetzer (6-1, 6-0).

She leads Seles 12-4 in head-to-head meetings.

Hingis, who held the No. 1 ranking for a record 73 consecutive weeks until injuring her ankle last October and undergoing surgery, says the unscheduled break did her some good. It took her mind off the grind of touring and helped her concentrate on improving her game.

"I think I've reached some stage that I haven't been before," Hingis said.