Defending champion Andy Roddick reached the semifinals at Queen's after struggling to beat Sebastien Grosjean of France 6-4, 7-6 (5) Friday at the Wimbledon tuneup event.
Top-seeded Lleyton Hewitt slumped 7-6 (4), 6-3 against Ivo Karlovic of Croatia, leaving the second-seeded Roddick favorite to take the title and join Hewitt and John McEnroe as the only players to win Queen's three straight years.
Roddick will play fourth-seeded Radek Stepanek next, after the Czech ousted France's Richard Gasquet 3-6, 6-1, 6-2. Karlovic meets Sweden's Thomas Johansson, who got past third-seeded Tim Henman, 6-4, 6-4.
"It feels good -- Seb's had really, really good results on the grass the last couple years," Roddick said. "It was a tough draw for both of us. I'm just excited to be through and excited that my preparation's gone well for Wimbledon."
Grosjean, who fought off five match points to defeat James Blake on Thursday, often played the crisper shots and showed greater skill at the net.
The Frenchman earned the first break point of the match at 2-2, but he made a forehand error and later lost the opening set with consecutive double-faults.
Two-time defending champion Roger Federer beat Philipp Kohlschreiber 6-3, 6-4 to reach the semifinals of the Gerry Weber Open.
Federer extended his winning streak on grass to 27 matches, the second longest in the open era after Bjorn Borg's 41 in a row from 1976 to 1981.
In other quarterfinals, second-seeded Marat Safin, still playing through knee pain, beat Olivier Rochus, 6-4, 7-6 (4) and seventh-seeded Tommy Haas defeated Juan Carlos Ferrero 6-2, 7-5 to set up a semifinal showdown with top-ranked Federer.
Safin will play fourth-seeded Guillermo Canas, who defeated Rainer Schuettler 6-4, 6-4 for a last-four berth in the 680,000-euro warmup for Wimbledon.
Federer is preparing for an attempt on a third straight Wimbledon title. Kohlschreiber was playing his first tournament on grass.
Top-seeded Maria Sharapova of Russia struggled with a cold and a thigh strain but still advanced to the final of DFS Classic after beating Eleni Daniilidou of Greece 7-5, 2-6, 6-1.
Sharapova, who won the Wimbledon warmup last year, needed an injury time out in the second set to treat her right thigh.
"There's no problem," Sharapova said. "Next week I will have a whole week off, so there's plenty of time to recover before Wimbledon."
Wimbledon, the granddaddy of all Grand Slam events starts on June 20.
Also, fifth-seeded Tatiana Golovin of France downed Anna Chakvetadze of Russia 6-4, 7-6 (3), and third-seeded Jelena Jankovic of Serbia-Montenegro topped Mashona Washington of the US 6-2, 6-4.
In the other quarterfinal, American Laura Granville defeated Tamarine Tanasugarn of Thailand 6-4, 6-3.