"I think it was a good match really, with long rallies," said Federer. "I thought that I played much better. I'm not sure if the stats showed it, but I felt [that] I served better. I'm really pleased how I felt this morning, my shoulder is a little sore having served a lot against [Taylor] Fritz. But that's exactly the kind of thing I need to feel having gotten back onto the match courts."
Federer improved to 7-0 lifetime against Mayer, who saved one set point at 5-6, 30/40 in the first set. Federer also recovered from 15/40 and saved three set points at 5-6 in the second set.
Top seed Federer will play the newest member in the Top 10 of the Emirates ATP Rankings, No. 7-ranked Dominic Thiem, in Saturday's semi-finals. "I'm now really excited about the semi-final against Thiem, who has had a great run this year," said Federer. "It will be a tough match, but I hope my experience will help me."
Third seed Thiem improved to 43-11 on the year, which includes three ATP World Tour titles, after he defeated 2002 champion Mikhail Youzhny 3-6, 6-4, 7-5 in one hour and 51 minutes.
"It was my best match on grass so far, against a very good and experienced player on this surface," said Thiem. "It was a very close match and it would have gone in any direction. [Looking ahead] it's tough to play Roger on any surface, but especially on grass."