MUNICH, Germany (AP) -- Defending champion Venus Williams, two points away from defeat, rallied to beat top-ranked Martina Hingis 6-2, 6-7 (6-8), 9-7 today to reach the final of the $6.7 million Grand Slam Cup.

In winning, Williams avenged a semifinal loss to Hingis at the U.S. Open three weeks ago.

``I don't believe in revenge,'' she said. ``No matter what happened, I still lost at the U.S. Open.''

In Sunday's final, worth $800,000 to the winner, Williams could face her younger sister Serena, the U.S. Open champion. Serena Williams played Lindsay Davenport in the second women's semifinal today -- in another repeat of the U.S. Open.

In a men's quarterfinal, Greg Rusedski fired 19 aces in beating Yevgeny Kafelnikov, the Australian Open champion, 7-5, 7-6 (8-6).

Kafelnikov, No. 2 in the world, came here from Australia, where he lost both singles matches in Russia's Davis Cup defeat to Australia.

Rusedski's semifinal opponent will be Andrei Medvedev, the French Open finalist, who beat Richard Krajicek 7-6 (7-5), 6-4. In the other semifinal, Tommy Haas plays Thomas Enqvist.

The tournament is the most lucrative in the world. It invites 12 men and eight women with the best records in the four Grand Slam events of the year.

Neither of the two Grand Slam champions present here, Andre Agassi and Kafelnikov, made it to the semifinals.

But for the first time since Wimbledon 1992 the top four players made it to the semifinals of a woman's tournament.

Hingis is No. 1, Davenport No. 2, Venus Williams No. 3 and her sister No. 4.

In an often electrifying showdown between two 19-year-olds that took 2 hours, 31 minutes, Venus Williams had to overcome her erratic play and rely on her big serve and power against Hingis.

Hingis celebrated her 19th birthday Thursday with a visit to the Oktoberfest, but she said this was not the cause of her slow start.

``I just didn't understand in the beginning what was happening,'' Hingis said. ``It was almost embarrassing.''

Williams was all over Hingis at the start, hitting powerful winners and firing aces.

Williams led 4-1 in the second set before Hingis got back into the match.

Hingis won 10 of 11 points as she rallied to 4-4 and took four straight games to lead 5-4.

``I made a lot of unforced errors,'' Williams said. ``I didn't hold serve at all.''

It went to a tiebreaker and Hingis saved a match point with a volley. A forehand error by Williams gave Hingis a set point and she took it with a brilliant passing shot.

Williams trailed 4-1 in the third set when she started putting pressure on Hingis. Williams got to 4-4, then dropped serve again and trailed 5-4.

Hingis was two points away from winning, but was unable to serve out the match, with Williams rifling two tremendous ground stroke winners.

In the final game of the match, Hingis fell behind 0-30. On the next point, Williams retrieved everything Hingis fired at her.

Forehand, backhand, from one corner to the other, Williams chased down everything. She switched momentum at the first opportunity, sending Hingis to a corner with a good volley. Hingis sent a lob that sailed long and Williams had three match points.

She needed only one, with Hingis sending a backhand long.

``I was down, I didn't want to lose,'' Williams said. ``I wanted to come out the victor for once.''

Hingis said she let Williams off the hook. ``... Two points away from the win.''

``If you lose a match like I did today, you have a little to think about what's going to happen in the future if you want to stay in the top,'' Hingis said, admitting that she had practiced little since losing the U.S. Open final to Serena Williams.

Williams finished with 18 aces, but also had 12 double-faults. Hingis had no aces, but only one double-fault and 23 unforced errors compared to 56 for Williams.

Williams, who had lost the previous two matches against Hingis, now is 4-8 against her.