Roger Federer advanced to the Gerry Weber Open quarter-finals on Thursday following an awkward game against Czech qualifier Jan Vacek.
The five-time defending Wimbledon champion saw off his opponent in straight sets 7-5 6-3, yet his 56th consecutive win on grass was harder to come by than expected.
It was not until the final game of the first set that world number one Federer began to fire, breaking his opponent for the first time.
Vacek saved three break points in his next service game at the start of the second set and matched the Swiss maestro for six games, the score standing at 3-3 before Federer won 12 of the next 14 points to secure passage to the last eight.
Next up for Federer is a meeting with last year's finalist Marcos Baghdatis, who overcame a slow start to defeat Frenchman Fabrice Santoro 6-3 6-3.
Also on Thursday, Nicolas Kiefer delighted his home crowd with a hard-earned 6-2 5-7 6-3 victory over Russia's Mikhail Youzhny.
The German won the decisive break in the sixth game of the third set to set up a quarter-final meeting with Frenchman Michael Llodra, who edged Belgian Steve Darcis 7-6 (8/6) 7-6 (7/3).
