Tennis Roundup : Horacio de la Pena, Unseeded Argentine, Upsets Wilander

Top-seeded Mats Wilander fell victim to the extreme heat and unseeded Horacio de la Pena Friday in the quarterfinals of the $415,000 U.S. Pro Tennis Championships at Brookline, Mass.

Wilander, heavily favored to win the tournament at Longwood Cricket Club, lost, 7-6, 6-1, on the clay center court, where temperatures were estimated to be more than 100 degrees.

Wilander, who had defeated the 21-year-old Argentine in straight sets in their only previous meeting, in 1986, had won the U.S. Pro championships twice in the last three years. Wilander is ranked No. 3 in the world, De la Pena 126th.

No. 2 Andre Agassi was upset, 6-1, 6-4, by No. 8 Thomas Muster, and No. 13 Lawson Duncan ousted injured No. 5 Aaron Krickstein, 7-5, 6-2.

Eliot Teltscher of Palos Verdes Estates came from behind to beat Miloslav Mecir of Czechoslovakia, 6-7, 6-3, 6-4, and advance to the semifinals of the $200,000 Gunze World tournament at Osaka, Japan.

Teltscher became the third American to advance to the men’s singles semifinals today, joining Tim Mayotte and Jimmy Connors.

Teltscher will face Mayotte, and Connors, who is coming off a disappointing showing at Wimbledon, will play Anders Jarryd of Sweden.

At Newport, R.I., Vijay Amritraj of India upset second-seeded Peter Lundgren of Sweden, 6-3, 4-6, 6-2, in a quarterfinal match of the Volvo Tennis Hall of Fame Championships.

Amritraj, 34, will meet fourth-seeded Wally Masur of Australia in a semifinal match today. Masur eliminated Kelly Evernden of New Zealand, 7-6, 6-0, in the other quarterfinal match.