Roger Federer bounced back from his crushing French Open final defeat to advance into the second round of the Halle Open with a 6-4, 6-2 win over German Michael Berrer on Wednesday.
The Swiss, a four-time winner of the grasscourt tournament in Halle, brushed aside Berrer to notch up his 55th consecutive win on the surface.
Defending champion Tomas Berdych of the Czech Republic, seeded three, suffered a 6-2, 7-5 second-round loss to Sweden's Robin Soderling, who pounded down 13 aces.
Second seed James Blake of the United States had an early scare against his German opponent Benjamin Becker, losing the first set, before recovering for a 4-6, 7-5, 6-3 win.
Germany's Phillip Kohlschreiber edged out compatriot Tommy Haas 7-5, 5-7, 7-6 to reach the last eight.
Andreas Beck won a battle of two German left-handers to book his place in the quarter-finals with a 6-7, 7-6, 6-1 victory over Mischa Zverev.