Mark Philippoussis made a surprising, but greatly welcomed, appearance at Australia's Davis Cup training shortly after stepping off a flight from America.

After casting an approving eye over hard-working duo Lleyton Hewitt and Philippoussis, captain John Fitzgerald was guardedly optimistic about Australia's chances of beating Spain in next week's final.

"We think we can do it," he said.

"We're here preparing, trying to get into a good frame of mind early and trying to peak at the right time."

Fitzgerald added he was "very wary of any opposition we play."

"I was very wary of Roger Federer (in the semi-final against Switzerland) and it panned out to be a pretty close tie.

"We're very wary of the Spanish. They have an incredible amount of depth, a wonderful team with highly ranked players who have had a lot of experience at this level.

"So under any conditions they're going to be hard to beat - but we think we can do it," he said.

Fitzgerald said that if Hewitt felt he was in peak condition by the middle of next week he would wind down his training.

Philippoussis joined Hewitt on the practice courts after spending last week as the reserve for the Masters Cup in Houston, where he didn't get a match.

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