ATP Gerry Weber Open: Four-time winner Roger Federer wins 6-0 6-0
Roger Federer recorded just the second 'double bagel' of his career to reach the semi-finals of the Gerry Weber Open.
Last Updated: 15/06/13 4:19pm
The 17-time Grand Slam champion destroyed world No 156 Mischa Zverev 6-0 6-0 in just 39 minutes of action in Halle.
The only other time Federer produced the same result was against Argentine Gaston Gaudio at the Masters Cup in Shanghai in 2005.
"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."
Top-seeded Federer will next play German veteran Tommy Haas, who beat him in last year's final, after the veteran German saw off France's Gael Monfils 6-7 (4-7) 6-3 6-3.
Federer, 31, who is searching for his first title of the year, now has 41 wins and just five defeats at Halle where he is also seeking his sixth title - his favourite tune-up for Wimbledon.