Fifth-seeded Kent Carlsson of Sweden surprised Yannick Noah, 4-6, 6-1, 6-4, in a two-hour battle Friday, and Haiti's Ronald Agenor upset Andre Agassi, 6-3, 6-1, in just 53 minutes to reach the semifinals of the Italian Open tennis championships at Rome.
Top-seeded Ivan Lendl struggled again but won a prolonged quarterfinal match over unseeded Jaime Yzaga of Peru, 6-2, 4-6, 6-2.
In the final quarterfinal, 14th-seeded Guillermo Perez-Roldan of Argentina upset No. 6 Andres Gomez of Ecuador, 6-2, 6-3.
The 18-year-old Perez-Roldan will face Agenor today in the semifinals.
The unseeded Agenor, who upset defending champion Mats Wilander in the third round, ended Agassi's 14-match winning streak.
Agenor, 23, ranked 45th in the world, ran Agassi, 18, of Las Vegas, around the slow red clay with a sharp forehand.
Agassi, who came to Rome after two straight clay-court tournament victories, said he was exhausted.
"My legs really hurt," he said. "If I had to run after every ball, I would have had to be carried out on a stretcher."
Carlsson, a clay court specialist, hadn't beaten Noah in three previous matches.
And it appeared that Noah, ranked eighth in the world, would beat Carlsson again as he broke out to a 5-1 lead on his way to winning the first set.
But the tide changed after Noah aggravated an injury to his right knee while leaping for an overhead. A trainer sprayed the knee, and Noah put on a leg brace.
The 20-year-old Carlsson capitalized on numerous unforced errors by Noah to take the second set.
Noah led, 4-3, in the final set, winning 11 straight points during one stretch.
But Carlsson won the next nine points and served out the match, ending it with a cross-court forehand passing shot.
In the semifinals, Carlsson will face Lendl, who broke serve four times on the way to winning his first set in 40 minutes. He finished with an ace.
But the 20-year-old Yzaga, ranked 65th in the world, used his low slice backhand to force Lendl into errors in the second set, breaking in the 10th game to close out the set.
After the two were tied, 2-2, in the final set, Lendl broke in the fifth game and never relinquished another game to finish the match.
Top-seeded Steffi Graf defeated Nicole Provis of Australia, 6-0, 6-2, to advance to the semifinals of the $300,000 West Berlin tournament.
In other matches, West Germany's Sylvia Hanika beat Radka Zrubakova of Czechoslovakia, 6-4, 3-6, 6-1, and Helena Sukova of Czechoslovakia downed Mary Joe Fernandez, 7-6, 6-0.