World number one Roger Federer [Images] and Australian Open champion Maria Sharapova [Images] are eager to rediscover their best form at this week's Pacific Life Open in Indian Wells after shrugging off viral problems.

Federer, who has competed in only two tournaments this season, succumbed to mononucleosis (glandular fever) at the end of last year.

Sharapova, who clinched the 18th WTA title of her career at last month's Qatar Open, was forced to pull out of the Dubai Championships two days later due to a viral illness.

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The duo appear to have shaken off their respective ailments and return this week to the imposing, state-of-the-art Indian Wells Tennis Garden where they both triumphed in 2006.

"It's always exciting to come back to a place where I've won," three-times champion Federer told reporters in the build-up to the opening Masters Series event of the season. "I have great memories and the stadiums are great here.

"It's kind of a relaxing week and, if you're playing good tennis, it's even more enjoyable."

The 26-year-old Swiss, a winner of 12 Grand Slam singles titles, accepts he needs to improve his fitness after he was finally diagnosed with mononucleosis after the Australian Open in January.

"I already feel strong again but the main issue now is to get 100 percent fit and make up for all the training I missed," Federer told his web site.

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"I have quite some catching up to do in terms of fitness as I am not in the physical state I would normally be in at this time of the year."

Federer was beaten in the first round in Dubai last week by Briton Andy Murray, his first match since losing to Serb Novak Djokovic in the Australian Open semi-finals.

AIR MILES

The globe-trotting Sharapova, who racked up around 50,000 air miles in January and February, decided to take a week's holiday after withdrawing from Dubai.

"I felt my body needed a rest," said the 20-year-old Russian, who attributed her viral problems to her gruelling tournament schedule.

"I think it's just a lot of flying and one way or another it's going to take a toll. After taking a week off my goal is to come out with a fresh frame of mind."

Sharapova, who claimed her third Grand Slam title at the Australian Open, won the 2006 Pacific Life Open by crushing compatriot Elena Dementieva 6-1, 6-2 in the final.

Predictably, Sharapova and Federer were the tournament favourites at Indian Wells last year but were knocked out in the fourth and second rounds respectively.

Spaniard Rafael Nadal [Images] went on to win the men's title while Slovakia's Daniela Hantuchova [Images] took the women's crown for a second time. Both are back this week to defend.

The tournament draw will be released on Tuesday and Federer, who has spent a record 215 consecutive weeks at the top of the men's rankings, is expected to be seeded one.

His main rivals in the men's event, which starts on Thursday, include Australian Open champion Djokovic, Russian world number four Nikolay Davydenko and sixth-ranked American Andy Roddick [Images], who won the Dubai title on Saturday.

Among the leading contenders in the women's competition, starting on Wednesday, are world number two Ana Ivanovic of Serbia, third-ranked Russian Svetlana Kuznetsova and Serbia's Jelena Jankovic, the world number four.

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