Andy Roddick [Images] is banking on his booming serve and improved court speed to help him beat world number one Rafael Nadal [Images] in Saturday's semi-final of the ATP event at Indian Wells.

The American trails Nadal 4-2 in career meetings but the former U.S. Open champion has been encouraged by a storming start to this season that included his 27th ATP title in Memphis.

"It's a difficult match-up for anyone," Roddick told reporters after booking his place in the last four with a 6-3 6-2 demolition of defending champion Novak Djokovic [Images].

"He (Nadal) seems to like this surface and it probably favours him. But with the way I serve, I think I'm always in there with a shot.

"I'm returning better and I'm able to mix it up with my returns. We'll see. I'll obviously have to play very well."

Roddick recruited fellow American Larry Stefanki as his coach in November and has clearly benefited from a rigorous fitness regime over the last four months.

"There's definitely been a difference," the 26-year-old said. "I feel like I'm moving a little bit better.

"Getting in better shape has allowed me to give myself more of a chance playing different ways. I know I can get to balls and I can possibly do something when I'm there so I'm not forced to go for broke on every shot. It gives you options."

IMPRESSIVE FORM

Top seed Nadal, who won the 2007 Indian Wells title and is arguably the quickest player around the court in the men's game, acknowledged Roddick's impressive start to this season.

"He's playing really well," the Spanish left-hander said after crushing Argentinean Juan Martin Del Potro 6-2 6-4.

"He started the season very well. Semi-finals in Australia [Images], he played the final in Doha, too, and he won in Memphis. It's going to be a really tough match.

"I have to play very well," added Nadal, who has captured three of the last four grand slam singles titles. "I must serve well if I want to win and be focused all the time, play aggressive on the return and play right.

"He can surprise you. You go on court and you know he's serving big power and he's gonna have big forehands. He goes aggressively to the net.

"But in the end, every match is completely different. The matches start from 50 percent for everybody tomorrow."

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