Roger Federer will face Florian Mayer in the quarter-finals of the German Tennis Championships after a 6-4 6-3 win over Jan Hajek.
Federer, the top seed at the Hamburg event, took little over an hour to beat the Czech qualifier despite squandering 10 of his 13 break points, including five match points in the eighth game of the second set.
The 17-time grand slam champion one is playing with a new, larger racquet in a bid to end a slump which saw him eliminated second round of Wimbledon./
"I guess it's to a degree some more getting used to, just to see how it reacts on every single shot," he told the ATP's official website.
"Clearly it reacts better to some shots. But it's important not to think of it the whole time, not to talk about it all the time, but more just sort of go with it, fight for every point, have the right mindset, be optimistic about playing here now and wanting to achieve a good result and that's what I'm doing."
Home hope Mayer defeated 11th seed Feliciano Lopez 7-6 (7-1) 6-2 to line up a meeting with Federer.
Second seed Tommy Haas also progressed on home soil as he defeated Carlos Berlocq 6-2 6-4 to set up a quarter-final with Fabio Fognini, who moved into the last eight with a 6-2 6-4 win over Marcel Granollers.
Wimbledon semi-finalist and fourth seed Jerzy Janowicz had a bad day as he was forced to retire from his match against Fernando Verdasco due to a right arm injury when the Spaniard was leading 7-5 4-0.
Verdasco will face qualifier Federico Delbonis in the last eight after the Argentinian defeated Dmitry Tursunov 6-4 6-3.
Elsewhere, third seed Nicolas Almagro eased into the quarter-finals with a 6-2 6-3 win over Guillermo Garcia-Lopez. He will play fifth seed Juan Monaco, who needed three sets to beat Benoit Paire 6-3 2-6 6-2.