Milos Raonic of Canada defeated Zhang Ze of China 6-1, 6-1 Wednesday to set up a possible quarter-final with five-time Gerry Weber Open champion Roger Federer.
Raonic made short work of the 217th-ranked qualifier in the second round of the grass-court tournament, breaking Zhang in the fourth game and taking just 20 minutes to win the first set, which he ended with his fifth ace.
The 21st-ranked Raonic had nine aces in the 52-minute win.
"I was very focused on myself, focused on my game, and making him feel as uncomfortable as possible and trying to make him adjust to me," Raonic said.
He will next face 16-time Grand Slam winner Federer or Florian Mayer of Germany, who meet on Thursday.
Federer has beaten Raonic in two compelling three-set matches this year, most recently last month at the Madrid Open.
Third seeded Tomas Berdych of the Czech Republic also reached the quarter-finals after beating Viktor Troicki of Serbia 6-3, 6-2.
The No. 7-ranked Berdych did not face a break point on serve during an-hour long match against Troicki, who is ranked No. 33.
Mikhail Youzhny of Russia eliminated the fourth-seeded Alexandr Dolgopolov of Ukraine 6-4, 3-6, 6-3.
"Today it was close, one break each set, and I was a little bit lucky. On grass you have to be a little bit lucky," Youzhny said.
The Russian will next play Radek Stepanek after the 33-year-old Czech overcame a spirited performance from 21-year-old Cedric-Marcel Stebe of Germany 6-4, 6-4.
Seven-time French Open champion Rafael Nadal teamed up with compatriot Marcel Granollers to defeat Troicki and Michal Mertinak of Slovakia 5-7, 6-2, 10-8.
"I really want to make an optimal start to the grass-court season here," Nadal said after the doubles match.
The 11-time Grand Slam winner will open in singles on Thursday against Lukas Lacko of Slovakia.