Roger Federer says he's learned to hone his kamikaze-like aggression, and that could be bad news for Stan Wawrinka after the pair set up an all-Swiss U.S. Open semifinal clash with respective straight-sets wins on Wednesday.
Federer, ranked second in the world, has yet to lose a set this tournament after dispatching Richard Gasquet in a lopsided 6-3, 6-3, 6-1 victory.
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Afterward, the 17-time major winner made no secret of his newest weapon — SABR, or Surprise Attack By Roger — as being one of the keys to his success. In fact, the 34-year-old has uncharacteristically made a living at the net this tournament, returning opponents' serves with newfound vigor.
"I think I have worked on my game moving forward, have been able to take the ball earlier, and I think I'm volleying better than I have the last 10 years," Federer told a news conference after his match. "I think I was volleying well coming up on the tour when I was younger because I was spending more time at net.
"Now because my serving is working quite well, you put those two things together, and standing in on the return as well, I think has changed the dynamics a little bit."
Wawrinka, who advanced on Wednesday with a 6-4, 6-4, 6-0 victory over Kevin Anderson, has played Federer only twice since their tense match at the ATP World Tour Finals in London in November, when reports of a rift between the pair emerged.
Federer historically has held the upper hand against his countryman, boasting a 16-3 head-to-head record, but Wawrinka has won two of the last five encounters since April last year, including a straight-sets victory at Roland Garros in May after having lost 11 consecutive matches prior to 2014.
Wawrinka, the tournament's No. 5 seed, believes he matches up equally to Federer.
"I think now we are both nervous when we enter the court," Wawrinka said. "Before it was only me. I was nervous because I knew I wasn't at his level, for sure. And now I think we can see that he was also nervous every time we play each other the past few years.
"That's a big difference, because that shows how much he knows that I can play at his level, how much he knows that I can try to play my game and not just try to react about what he's doing."