Indian Wells, California  - Roger Federer is optimistic about reversing losses to Andy Murray in the pair's last three matches when they meet in Saturday's semi-finals at the Indian Wells Masters.

In the six months since the Swiss claimed his 13th Grand Slam title over the Scot in the US Open final, Murray has risen to the occasion with victories in Madrid, Shanghai and Doha to start the year.

But the experienced Swiss reckons that it is merely a matter of a few fine adjustments before he resumes overturning a surprise 2-5 record against the world number 4.

"He's young, so you still have to figure him out a little bit. He's changing his game as time goes by. Every time you play him he plays a bit different."

World number 2 Federer said being a longtime target himself gives any challenger an instant edge. "For me it's different, he knows what to expect. That's the advantage of a youngster.

"I'm aware that he has beaten me more than I've beaten him, but on big occasions, I think I came through. I have to build on that and make sure I play tough and good match against him.

"Anything else is not going to do the job against him."

Federer won Indian Wells three years running 2004-2006 and last lifted a Masters 1000 title in China, late 2007.

"Last year was sort of kind of strange for me, I didn't win any. I wasn't 100 percent in shape, especially these two here, Indian Wells and Miami.

"Novak (Djokovic) and Murray and the other players did really well in the American hard court, where I think I really would have had a chance to win a few maybe."

Federer is playing for the first time since a back injury and the Australian Open finals defeat by Rafael Nadal.

Murray is also riding a wave of confidence with two titles this season.

"I've played him seven times, so we know each others' games pretty well. Obviously if I want to beat him I need to play one of my best matches.

"It's important to serve solid and make a lot of balls and not feel like you have to do, you know, anything special on each point to win against him." (dpa)