MELBOURNE, Australia — Serena Williams won her second straight Australian Open championship, ending Justine Henin's hopes of a Grand Slam title in her return from retirement with a 6-4, 3-6, 6-2 victory today.

Williams withstood a determined challenge from Henin before securing her fifth Australian Open title overall and 12th Grand Slam singles championship overall, tying Billie Jean King.

King was at the stadium on Saturday night to take part in a pre-match ceremony to honor the 40-year anniversary of Margaret Court's four Grand Slam tournament wins in 1970.

"Billie, we are tied," Williams said. "So I've reached my goal."

Williams' five Australian titles is the most by any woman in the Open Era, since 1968, surpassing the four held by Margaret Court, Evonne Goolagong Cawley, Steffi Graf and Monica Seles. Court holds 11 Australian Open titles overall, most coming before 1968.

Henin, who had most of the crowd support at Rod Laver Arena, couldn't match her fellow Belgian Kim Clijsters' feat of winning in her Grand Slam comeback tournament. Clijsters won last year's U.S. Open in her return from a two-year retirement after getting married and having a daughter.

Williams won the last four games to clinch the championship in just over two hours, falling on her back in celebration after match point.

"It was definitely a tough match mentally and physically," Williams said. "We were both out there to prove something, and I think we did at the end of the day."

It was an impressive run by Henin. She lost in the final of the Brisbane International tournament to Clijsters two weeks ago.

The unranked and unseeded Henin then beat four seeded players en route to the Australian Open final, including No. 5 and Olympic gold medalist Elena Dementieva in the second round.

"It's been a very emotional two weeks for me," said Henin, who put her hand on her heart as she thanked the crowd for support. "I thought it would never happen to me again. I'd like to congratulate Serena. She's a real champion."

Later, Henin said there was a feeling of disappointment, but accomplishment.

"It's just more than what I could expect, I just have to remember that," Henin said. "Even if it's quite soon after the match now, I'm sure there will be a lot of positive things I can think about in a few days. It's been almost perfect. Just the last step, I couldn't make it."

And she's certain now about her decision to come back on the tour.

"I was curious about what my level would be and how I was going to deal with just the atmosphere on and off the court, how it would feel," Henin said.

"I felt I took the right decision, so it's good enough for me already. I got the results also in the last four weeks — two finals. So I can be really happy about that."

Henin saved two break points to hold for 3-3 in a four-game run in the second set, winning 13 of the last 14 points in a dominant finish to the set. She maintained the superiority early in the deciding set, increasing that to 18 of 19 points before Williams held serve to even the third set at 1-1.

Williams, with her right thigh and left knee heavily taped as it had been for much of the tournament broke Henin to go up 2-1. The two then traded breaks, with Williams going up 3-2, a lead she never relinquished.

"I thought I was just giving it to her at that point," Williams said. "I didn't want to go out like that. I literally said to myself, 'I need to man up and start playing better.'"

Williams used an ace on her second serve to hold for a 4-2 lead, then broke again to move within a game of the title.

"It's good to have her back, it's exciting," Williams said of Henin. "She can definitely be No. 1, especially with our ranking system, if she keeps doing well."

The American holds an 8-6 edge in career meetings between the pair, including a 6-2, 6-0 win in Miami in 2008. At the time, it equaled the worst loss for a reigning No. 1, and Henin quit tennis two months later.

Henin won the Australian Open title in 2004. She quit during the 2006 final with stomach problems while trailing Amelie Mauresmo 6-1, 2-0.

Chris Evert and Martina Navratilova are Williams' next goal, with 18 majors each.

"Honestly, I'm just doing what I can. I obviously enjoy playing in Melbourne, clearly," Williams said. "I never thought I could catch up with Martina, because she's such an amazing champion." the title here three of the past four years and were losing finalists the two previous years.

American twins Bob and Mike Bryan won their fourth Australian Open doubles title, defeating Daniel Nestor of Canada and Serbian Nenad Zimonjic 6-3, 6-7 (5), 6-3 in the final.

The brothers have won the title four of the past five years. They have eight Grand Slam doubles titles, including two at the U.S. Open and one each at the French Open and Wimbledon.

The men's final between Roger Federer and Andy Murray will be held Sunday night, where Murray will attempt to become the first British man since Fred Perry in 1936 to win a Grand Slam major.

The Australian Open is Murray's 17th Grand Slam tournament, which is how many attempts Federer needed before winning for the first time at Wimbledon seven years ago against Mark Philippoussis.

Murray was beaten 6-2, 7-5, 6-2 in the U.S. Open final in 2008.

Two years later, the now 22-year-old Murray thinks he knows how to end the 74-year drought.

"I'm going to need to play my best match ever," Murray said Saturday. "That's what I plan on doing. If I do, I've got a good chance of winning."

Federer played in all four finals last year and will be appearing in his 22nd Grand Slam final overall, a record. He acknowledged that the pressure will be on Murray.

"I know what it takes (to win) and how to do it, which is definitely an advantage," Federer said. "I don't feel like the pressure's really on me having to do it again. I think he really needs it more than I do."