STUTTGART, Germany (AFP) — Roger Federer beat Florian Mayer 7-6 (7/2), 7-6 (7/1) yesterday to reach the Stuttgart grass court semi-finals, claiming another record in the process.

The world number three moved ahead of Ivan Lendl to stand second in career match wins with his 1,072 victories putting him behind Jimmy Connors (1,256).

Federer dispatched Germany’s Mayer for the seventh time without a loss as he advanced into a final-four showdown with Austrian Dominic Thiem, who recovered to defeat Russia’s Mikhail Youzhny 3-6, 6-4, 7-5.

Federer is playing for the first time in a month after suffering with back pain which forced him to skip the French Open.

“The feeling was better, I felt I was playing up and down the court more, coming to the net and seeing things a bit better,” Federer said.

“My serve was more consistent and accurate and I played two good tie-breakers. I’m very pleased, this was a step up from the last match.”

German seventh seed Philipp Kohlschreiber beat qualifier Radek Stepanek 6-4, 7-5 while Juan Martin del Potro overhauled French fourth seed Gilles Simon 6-7 (3/7), 6-3, 6-0.

Federer’s last Stuttgart appearance was a decade and a half ago when the event was an indoor Masters.

He advanced with 15 aces in 80 minutes to stand 13-4 on the season.

World number seven Thiem said he has achieved more this week on grass than he had imagined.

“It’s not nice to play Roger on any surface. He is the best on grass. Against him, I have no expectations.”

The 22-year-old said that beating an injured Federer a month ago on clay in Rome meant nothing.

“I can win on clay. That is my surface, and I feel very confident against almost all players,” he said.

“But grass is different for me. I’m unbelievably happy with this semi-final, anything that comes now is a big bonus.”

Thiem, a French Open semi-finalist, now stands 4-6 in his career on grass as he scored his first back-to-back wins on the lawns with 11 aces.

“This was the biggest win of my career on grass,” Thiem said after advancing in just under two hours over the 2002 winner at the Weissenhof Club when the event was played on clay.

“I won a tight match against a very good and very experienced grass player.

“There were a lot of ups and downs, I was close to losing in the second set with break points and at 5-5 in the third.

“I’m happy with my fighting spirit and happy with this win.”

Thiem dropped the opening set as he lost the eighth game.