Top-seeded Ivan Lendl continued to dominate Brad Gilbert, and defending champion Andre Agassi overcame a strained back to beat Aaron Krickstein Saturday in the quarterfinals of the Tournament of Champions.

Lendl beat Gilbert for the 15th time without a loss, 6-0, 6-1, and Agassi rallied in the final set to down Krickstein 6-1, 2-6, 6-3 at the West Side Tennis Club in Forest Hills.In other quarterfinals, eighth-seeded Michael Chang beat No. 15 Marcelo Filippini of Uruguay 6-4, 6-7 (2-7), 6-2, and Jaime Yzaga of Peru eliminated Diego Perez of Uruguay 6-7 (4-7), 6-0, 6-2.

The semifinals, which are scheduled for Sunday, will feature Lendl versus Agassi and Chang against Yzaga. The final has been pushed back a day to Monday because rain washed out play on Friday.

Lendl needed only 58 minutes to eliminate Gilbert, ranked 17th in the world. "The law of averages says he should beat me once or twice, but the way he carries himself on the court suggests to me that he doesn't think he can win," saidLendl, who has lost only 10 games in his first three matches.

Krickstein broke Agassi at love in the opening game of the third set and then held for a 2-0 lead. But Agassi won the next five games despite a stiff back that began bothering him early in the second set.

Agassi won the first set in 22 minutes, losing only one point on his serve and breaking Krickstein twice at love. But Krickstein took control midway through the second set with his deadly groundstrokes, winning five straight games after Agassi held to pull within 3-2.

After losing the opening point at 5-2 in the second set, Krickstein won 15 consecutive points and appeared to have command of the match. However, with a chance to go up 3-1 in the final set, he double-faulted and eventually lost the game. Agassi went on to break for a 4-2 lead and served out the match.

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At Hamburg, West Germany, top-seeded Steffi Graf of West Germany and Jana Novotna of Czechoslovakia won their semifinal matches Saturday in the $200,000 Hamburg Virginia Slims women's tennis tournament.

Graf, the top-ranked woman player in the world, struggled in the first set after blowing a 5-1 lead but rallied to win seven games in a row and crush Bettina Fulco of Argentina 6-4, 6-0. Novotna overcame an ankle injury to beat Arantxa Sanchez of Spain 7-6 (7-1) 3-6, 6-1.