Serena Williams of the US in action during the match against Romania's Simona Halep at the All England Lawn Tennis Championships at Wimbledon, Thursday, June 23, 2011

*Defending champion Serena Williams again had to come from a set behind to advance at Wimbledon.

Today, she beat Romania’s Simona Halep 3-6, 6-2, 6-1 to move into the third round of Wimbledon, staying on course for a fifth title.

After dropping the first set, Williams regained her renowned intensity and powerful shot-making to dominate the next two sets on Court 2. The winner of 13 Grand Slam singles titles is still searching for her form after a yearlong absence because of injuries and health issues.

From 4-2 in the second set, the seventh-seeded American won eight out of the last nine games to re-establish her supremacy.

It was the fourth consecutive three-setter Williams has played since returning last week at the Eastbourne grass-court tournament. She had been out for nearly a year after two foot operations and blood clots in her lungs.