Boris Becker said Sunday that he had turned a page with his victory in the final of the $492,500 Stella Artois indoor tennis championships in Milan, Italy.

"It proved I'm fit, that I'm 100 percent now. And it will help me to forget about Melbourne," said the 21-year-old West German, who made short work of unseeded Soviet Alexander Volkov 6-1, 6-2 at the Palatrussardi Arena."I am going into the next tournament with good memories," he added.

Becker, the top-seeded player in the Milan competition, was eliminated by Swede Jonas Svensson in the quarterfinals of the Australian Open last month.

On Sunday he won his first major Grand Prix tournament since the New York Masters last December. It was his second victory in Milan in three years.

Becker, who led West Germany to a sensational victory over Sweden in the 1988 Davis Cup final, dominated play Sunday before a sellout crowd of 7,000.

Becker struggled in his first three matches in the tournament but played at his best in Saturday's semifinal against third-seeded American John McEnroe, beating him 6-2, 6-3.

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At Memphis, Tenn., Brad Gilbert served warning that he is ready to make a major move up the tennis rankings ladder in 1989.

Gilbert, a finalist two weeks ago in Chicago, dominated Johan Kriek for two sets Sunday and then captured the singles title in the $415,000 Volvo Tennis Indoor Championship when a groin injury forced Kriek to retire.

"It was an unfortunate way to end the tournament, but it feels good to be back in the winner's circle again," said Gilbert, the No. 6 seed in the Indoor and currently ranked 19th in the world.

Gilbert had little problem handling No. 16 Kriek's power game, winning the first two sets by identical 6-2 scores.

"I played consistently. I didn't really go for a lot of winners. I just played the ball back," said Gilbert, who defeated Kriek for the sixth time in seven meetings.

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And at Fairfax, Va., Steffi Graf of West Germany won the first 20 points, then capitalized on two late service breaks in the second set and captured the $300,000 Virginia Slims of Washington with a 6-1, 7-5 victory over Zina Garrison.

Graf, the world's top-ranked player, won 25 of the 29 points in the first set. Garrison did not register a point until the sixth game of the match, and could not muster a point off Graf's serve until the second set.

Garrison made a match of it in the second set, holding serve throughout the first eight games and getting a service break to pull into a 5-5 tie.

Graf, who has not lost a set in 12 matches in 1989, broke the deadlock by notching a service break at 30, then holding serve at 15. The final point of the 65-minute match came when Garrison drilled a forehand well past the baseline on Graf's second serve.