Unseeded Cristiano Caratti of Italy upset top-seeded Ivan Lendl, 6-4, 1-6, 7-6 (7-3), in the Milan Indoor tournament to advance to the quarterfinals. Caratti, 20, is No. 79 in the world. Lendl, a three-time Milan winner, is third.

In the tiebreaker, Lendl fell behind by 0-3 but fought back to 3-3 before losing four consecutive points to Caratti.

Third-seeded Andrei Chesnokov of the Soviet Union was beaten by Sweden's Jan Gunnarson, 6-4, 6-3.

Aaron Krickstein, the only American to reach the quarterfinals, will face Germany's Carl-Uwe Steeb, who defeated Karel Novacek of Czechoslovakia, 4-6, 7-6, 6-4 . . .

Third-seeded Brad Gilbert of the United States beat Alexander Mronz, a German player with a 115 mph serve, 6-3, 6-3, to reach the quarterfinals of the Volvo-San Francisco tournament.

Top-seeded Andre Agassi turned back Udo Riglewski, another hard-serving German, by 3-6, 6-4, 6-3.

In a three-hour match between former Stanford stars, Dan Goldie fought off a match point and upset fifth-seeded Tim Mayotte, 2-6, 7-6 (8-6), 7-5. It was Goldie's first win over Mayotte in four meetings.