Roger Federer remains on course for a ninth title at the Gerry Weber Open in Halle after defeating Florian Mayer in the quarterfinals.
The 35-year-old has found his feet on grass at the most successful tournament of his career after his shock early loss to Tommy Haas in Stuttgart.
He needed just an hour and six minutes to see off German Mayer 6-3, 6-4, serving 11 aces and taking two of his 12 break points.
In the semifinals, Federer will face Karen Khachanov, who won the battle of the young Russians against Andrey Rublev 7-6 (10/8), 4-6, 6-3.
France's Richard Gasquet is also through to the last four after a 6-1, 3-6, 6-1 victory over Robin Haase.