Twice former champion Serena Williams [Images] recovered from a miserable start on Thursday to defeat Italian Mara Santangelo 2-6, 6-3, 6-2 and take her place in the third round at Wimbledon [Images].

The fourth seed, plagued by injury this season after her triumph in the Australian Open [Images], looked a pale shadow of her powerful self at the start.

Wimbledon 2005: Complete coverage

Williams, winner of seven grand slam titles, started tamely against an opponent who refused to be overawed.

Her ground strokes lacked their usual fluency, her booming serve deserted her. Shoulders slumped, she could not believe her own patchy form.

Santangelo, who is ranked 120 places below Williams in the world, raced to a 4-0 lead.

Williams saved three set points at 5-1 but Santangelo then served out for the first set.

In the second set, the controlled fury of Williams' power play returned with a vengeance as she imposed her will on the willowy Italian.

Her grunts reached new heights of determination and her accuracy finally returned.

As evening shadows gathered on centre court, the Italian's resistance crumbled in the deciding set which Williams won easily.

But it took one hour and 36 minutes to stamp her authority over a lowly opponent who should have been dismissed in half the time.

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