(CNN) -- Stanislas Wawrinka has had little time to rest on his laurels after winning his first grand slam title but the new Australian Open champion rounded off a superb day for Switzerland as they took a commanding 2-0 lead over Serbia in a Davis Cup tie in Novi Sad Friday. Wawrinka battled jet leg after the long haul flight from Melbourne -- where he had beaten Rafael Nadal in Sunday's final -- to see off Dusan Lajovic 6-4 4-6 6-1 7-6. Earlier, former world number one Roger Federer, a late inclusion in a strong Swiss line-up, beat Ilija Bozoljac 6-4 7-5 6-2 to give them the advantage.
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Stanislas Wawrinka wins first match since claiming Australian Open
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Helps Switzerland to 2-0 lead over Serbia in Davis Cup first round tie
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Roger Federer wins opening rubber for Swiss against Serbia team without Novak Djokovic
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Maria Sharapova into semifinals of WTA tournament in Paris
@placeholder took the first set against world number 102 Lajovic, but was in trouble in the second as the Serbian leveled.
The new Swiss number one raced through the third set, but the fourth was again a struggle and he needed unforced errors from the inexperienced @placeholder in the tiebreak to close out the match.