TENNIS : Medvedev Records U.S. Pro Upset

BROOKLINE, Mass. — Soviet teen-ager Andre Medvedev outlasted third-seeded Jaime Yzaga of Peru, 4-6, 6-4, 6-3, in the second round of the U.S. Pro Tennis Championships on Thursday.

Medvedev raced to a 5-1 lead in the second set with solid net play at Longwood Cricket Club. But Yzaga, countering with passing shots, fought back to 5-4 before Medvedev won the set on a service break.

In another second-round upset, Tobias Svantesson of Sweden beat No. 2 Richey Reneberg, 7-5, 1-6, 6-2.

In other matches, No. 5 Jimmy Arias overcame shoulder pain to defeat Peter Nyborg of Sweden,6-4, 6-4.

“I cut down on the power of my serves and concentrated instead on placement. It worked,” Arias said. “Maybe I should do more of that.”

Seventh-seeded Andres Gomez of Ecuador battled to a 6-4, 4-6, 6-0 victory over Luke Jensen, and No. 8 Jim Grabb beat Tom Mercer, who withdrew in the third set with a sprained shoulder. The pair had split tiebreakers in the first two sets and Grabb was leading 2-1 in the third.