Five-time champion Roger Federer and reigning titlist Tommy Haas will meet Saturday in a rematch of last year's final at the $900,000 Gerry Weber Open, a grass-court Wimbledon tune-up.
The top-seeded former world No. 1 Federer double-bageled German Mischa Zverev, while a third-seeded Haas fought back to beat former top-10 Frenchman Gael Monfils 6-7 (4-7), 6-3, 6-3 in Friday's quarterfinal action at Gerry Weber Stadium. Federer destroyed Zverev in 39 minutes for the second 6-0, 6-0 victory of his career, while Haas survived a 14-ace effort from Monfils in 1 hour, 54 minutes.
Federer tallied his first double bagel against Gaston Gaudio at the 2005 Masters Cup in Shanghai.
"It's not something which is easy to do. You never go into a match aiming for that score," Federer said. "I was very surprised that it happened today, especially on grass.
"I think it is disappointing for a serve-and-volley player to go down like this. It shows also how easy it is to hit passing shots or returns today.
"I hope he doesn't take it too badly," Federer added. "I just had a pretty easy time picking up his serve, and I must have made a ton of returns."
The reigning Wimbledon champion Federer has appeared in seven Gerry Weber finals, capturing the five titles along the way.
The one-time world No. 2 Haas stunned the seven-time Wimbledon champion Federer in last year's Halle finale and also titled here in 2009.
Federer is 10-3 lifetime against Haas. including a 2-1 record in Halle.
Also on Day 5, second-seeded Frenchman Richard Gasquet dismissed eighth-seeded German Florian Mayer 6-3, 7-6 (7-4) and Russian veteran Mikhail Youzhny took out sixth-seeded German Philipp Kohlschreiber 6-3, 6-2. Kohlschreiber titled here in 2011 and was the runner-up in 2008.
Gasquet will face Youzhny in the other semifinal.
This week's winner will earn $163,000.