Ivan Lendl rallied to beat 18-year-old David Wheaton, 6-7, 6-3, 6-2, Thursday and move into the quarterfinals of the $232,000 D.C. tennis tournament at Washington.
Boris Becker and Jimmy Connors also advanced. Becker defeated John Ross, 6-4, 6-2, and Connors downed Jim Pugh, 6-3, 6-1.
Lendl needed 2 hours 29 minutes to eliminate Wheaton, a member of the 1985 Junior Davis Cup team who is ranked 428th in the world.
"I just tried to stay with him no matter what happened," said Wheaton, the No. 2 junior player in the United States last year. "It worked out well in the first set."
Lendl had a chance to end the first set serving at 5-4, 40-15, but squandered the opportunity and eventually dropped the tiebreaker, 7-5.
Wheaton, from Minneapolis, won the set with a smash at the net after he handcuffed Lendl with a strong serve to his backhand.
After losing his serve to fall behind 1-2 in the second set, Lendl broke Wheaton's serve to pull even and then won four of the next five games.
Lendl opened the final set by breaking serve at 15, then coasted.
In order to conserve energy for his doubles match later in the afternoon, Lendl purposely let Wheaton win the seventh game, wrapping a towel around his neck for the final point. Lendl then served out the match at 15.
But Lendl eventually defaulted the doubles match, claiming he was suffering from heat exhaustion after enduring near 100-degree temperatures in his match against Wheaton.
Connors, meanwhile, broke Pugh's serve in the seventh and final games of the opening set, then used a break in the fourth game of the second set to take a comfortable 4-1 lead.
Connors will next play Todd Witsken, who routed Australia's Laurie Warder, 6-0, 6-1. Witsken, seeded 12th, knocked Connors out of last year's U.S. Open.
In other third-round matches, Marty Davis upset Johan Kriek, 6-4, 7-6; Brad Gilbert stopped Nigeria's Nduka Odizor, 6-4, 6-4, and Jimmy Arias eliminated Australia's Simon Youl, 7-6, 6-3.
At Vancouver, Canada, Hana Mandlikova and Helena Sukova combined for a 7-6, 6-2 victory over Helen Kelesi and Jill Hetherington to give Czechoslovakia a 2-1 victory over Canada in the Federation Cup quarterfinals.
Canada had taken a 1-0 lead when Kelesi upset Sukova, 4-6, 6-1, 6-2. But the Czechs avoided elimination when Mandlikova beat Carling Bassett, 6-4, 6-1.
West Germany advanced with a 2-1 victory over Argentina and will play Czechoslovakia in the semifinals Saturday.
Steffi Graf defeated Gabriela Sabatini 6-4, 6-4, after Claudia Kohde-Kilsch beat Bettina Fulco, 6-2, 6-2.
Argentina salvaged the doubles when Sabatini and Mercedes Paz beat reserves Bettina Bunge and Silke Meier, 6-7, 6-1, 6-2.
In the remaining quarterfinals, the United States faces England today, while Bulgaria plays Australia.
At Bastad, Sweden, heavy rain throughout the day forced all the matches in the $202,500 Swedish Open to be postponed.
Weather permitting, the last four second-round matches and the quarterfinals in the singles will be played today.