Top-seeded Boris Becker was upset by Czechoslovakia's Karel Novacek 6-3, 6-3 today in the quarterfinals of the Austrian Open.
Novacek, ranked 37th the world, needed just over an hour to oust Becker, who often has problems on clay courts and was well below his usual form.
Becker was whistled and jeered as he left the court by many in the crowd of 6,500, including his fellow West Germans.
Novacek's opponent in the semifinals will be Austrian Horst Skoff, who defeated compatriot Thomas Muster 6-4, 6-2.
Becker, now No. 3 in world rankings, started strongly, taking a 3-0 lead.
But his game disintegrated. He repeatedly served double faults and netted or overshot on simple returns.
Becker lost nine games in a row, handing Novacek the first set in just 32 minutes.
The West German rallied only in the fourth game of the second set to hold serve to love. It wasn't enough to stop Novacek, who, serving at 5-3, snatched victory on his first match point when Becker drove a weak forehand into the net.
"I can't remember that Boris ever lost so many games in a row," said Niki Pilic, who heads West Germany's Davis Cup team. "I don't know what got into him."
On Thursday, Becker played unevenly but managed to oust Sweden's David Engel, 6-4, 4-5, 6-0 to reach today's quarterfinal match.
In another upset, unseeded Horacio de la Pena of Argentina defeated Spain's Sergi Bruguera, seeded eighth, 6-4, 6-1.
Third-seeded Emilio Sanchez beat Soviet Andrei Cherkasov, the 11th seed, 6-1, 6-4.