Top-seeded Michael Stich double-faulted on match point and lost to Amos Mansdorf, 7-6 (7-5), 7-5, in the third round of the U.S. Pro Indoor tennis tournament Thursday at Philadelphia.
Second-seeded Pete Sampras, who won the U.S. Pro Indoor in 1990, barely advanced, beating No. 15 Stefano Pescosolido of Italy, 7-6 (7-0), 4-6, 6-4.
Aaron Krickstein, seeded 10th, rallied from a 5-0 deficit in the third set and won seven straight games to beat Rodolphe Gilbert of France, 3-6, 7-6 (7-3), 7-5.
Sixth-seeded Brad Gilbert beat qualifier Martin Laurendeau of Canada, 6-4, 6-3, and Jim Grabb advanced to the quarterfinals with a 7-6 (7-3), 6-4 victory over Todd Woodbridge.
Stich, the Wimbledon champion from Germany, had 13 service aces, but he also hit many shots into the net.
Stich said he was a victim of fatigue.
"It's the beginning of the year, and I feel really tired," he said. "I'm at a point where you should normally stop playing and take a break. But after all I did last year in the second half of the year, certain things are expected."
Said Mansdorf: "He actually had more chances than me. For him not to convert them, I think I was quite lucky. I don't care how he played; I played great."
Jim Courier and Stefan Edberg, the top two seeded players, won but upsets eliminated third-seeded Boris Becker and No. 4 Ivan Lendl in a $1 million tournament at Stuttgart, Germany.
Courier defeated Dutchman Richard Krajicek, 6-3, 3-6, 6-3, and Edberg swept past Austrian Alex Antonitsch, 6-1, 6-2.
Unseeded Jan Siemerink ousted Becker, 6-3, 6-4, and Alexander Volkov of Russia outlasted Lendl, 7-6 (7-4), 5-7, 6-1.
Top-seeded Zina Garrison advanced to the third round of the Virginia Slims of Oklahoma, beating Japan's Rika Hiraki, 6-2, 6-1, at Oklahoma City.
Second-seeded Gigi Fernandez advanced with a 7-6 (7-4), 6-1 victory over Robin White.
Third-seeded Lori McNeil advanced with a 6-4, 6-2 victory over Elna Reinach.
Top-ranked UCLA and No. 2 USC won matches on the first day of the National Collegiate Indoor Team Tennis Championship at Louisville, but No. 7 Pepperdine was upset by No. 12 Mississippi State, 5-4. The Waves lost two of three doubles matches.
The Bruins beat Tennessee, 5-1, and the Trojans topped North Carolina, 4-2.
Earlier, No. 3 Stanford edged No. 13 Harvard, 4-2; No. 4 LSU beat No. 14 California, 5-1; No. 6 Texas Christian beat host Kentucky, 4-2; No. 10 Notre Dame blanked No. 5 Florida, 6-0; and No. 11 Georgia upset No. 8 Miami, 4-2.