Defending Wimbledon champion Roger Federer made a seamless transition from clay to grass on Wednesday as he cruised into the quarter-finals of the ATP Halle Open after brushing aside German wildcard Cedrik-Marcel Stebe 6-3, 6-3.
Federer, who is using the tournament as a tune-up for the defence of his title at the All England Club later this month, needed just 67 minutes to see off Stebe in what was the Swiss star's first outing since losing to Frenchman Jo-Wilfried Tsonga in the last eight at Roland Garros.
Federer, a five-time winner at the ATP event in Germany but without a title to his name this season, came out firing immediately with a break of serve in the opening game as he raced 5-1 ahead, only to squander a chance to close it out before breaking Stebe for a third time to take the set.
A service break in the second game of the second set then proved decisive as Federer sealed his passage into the quarters, where he'll face another German in World No.156 Mischa Zverev, who beat Bosnia's Mirza Basic 7-6 (7/5), 6-3 earlier Wednesday.
Earlier, fourth seed Kei Nishikori of Japan was stunned by Russian veteran Mikhail Youznhy 6-1, 6-7 (4/7), 6-3 in the second round.
Youzhny, 30, will face one of German pair Philipp Kohlschreiber, the sixth seed, or Tobias Kamke in the next round.
The Russian reached the Halle semi-finals last season where he was beaten by Federer.
It was world number 13 Nishikori's opening match in the tournament having been given a first round bye.
And he was slow out in getting used to the grass as world number 29 Youzhny, who became an instant YouTube hit during Roland Garros after smashing his racket nine times against his chair in a fit during his defeat to Tommy Haas, breezed through the first set.
Nishikori, who reached the fourth round at the French Open, before losing to eventual winner Rafael Nadal, found his feet and battled with Youzny for more than two hours before finally succumbing to defeat.
"It's tough to play him in the first match. He started well and I was missing a lot," said the Japanese.
"I started playing well in the second set but in the last game he took his chance. I have to prepare for Wimbledon now."
Nishikori said he wished the grass court season was longer to give players more time to adapt to the little-used surface.
"It's not easy because it's played only a few weeks during the year. I like the idea of a longer season on grass. Wimbledon is everybody's dream to play."