Defending champion Lleyton Hewitt has been dumped out of Halle's ATP grasscourt tournament after he went down in straight sets to Philipp Kohlschreiber in Friday's quarter-final.
Kohlschreiber is into the semi-finals at Halle for the fourth time in his career after securing a 7-6 (7/4), 6-3 win over the former world number one in exactly 90 minutes.
The German smashed down 14 aces, compared to the Australian's nine, in a hard-fought match.
It was Kohlschreiber's strong serve which carried him to victory and he will play either France's Gael Monfils or fellow countryman Florian Mayer in the semis.
"Today, I could see an improvement in my game - everything was just fine and I often had a bit of luck on my side," said Kohlschreiber.
"I couldn't do much wrong.
"This match was good - although he is coming back from injury, Lleyton Hewitt is still one of the best players in the world.
"Now the bar has been set high. The next game will be hard, no matter who is on the other side of the net.
"Form on the day will decide the match."
Kohlschreiber is the second German definitely into Halle's last four after compatriot Philipp Petzschner earlier booked his place by knocking out eighth-seeded Canadian newcomer Milos Raonic.
In a tough last-eight match, Petzschner needed nearly two hours to prevail over 20-year-old Raonic and seal a 6-3, 6-7 (6/8), 6-3 win.
In Saturday's semi-final, the 27-year-old Petzschner will now meet either 2007 Halle winner Tomas Berdych - the top seed after Roger Federer's withdrawal on Monday - or Davis Cup winner Viktor Troicki of Serbia.
"It was a tight match on a knife edge. I nearly won it in the second set," said Petzschner, who also reached the semi-finals here last year.