Professional misery and personal heartache over the past two years drove Serena Williams [Images] right through the pain barrier to the Australian Open crown, the American said on Saturday.

The seventh seed staged a stunning comeback to beat Lindsay Davenport [Images] 2-6, 6-3, 6-0 at Melbourne Park before saying she had been through too much in the past two years to consider giving in to a back injury which struck at the start of the match.

The 2003 champion suffered the injury in the opening game of the final but bravely fought back to defeat world number one Davenport in a display of heart and determination.

"She was killing me in the first set but I just thought, 'Enough... I'm not going to lose," Williams said.

"Lindsay had me on the run, I was running for a ball on my backhand and my back went out. I'm not as young as I used to be," the 23-year-old smiled.

The remarkable comeback gave Williams her seventh Grand Slam title and her first since Wimbledon in 2003.

It was soon after that victory that Williams endured a bleak period in her life which included the death of one of her elder sisters, the separation of her parents and an extended lay-off after knee surgery.

She won tournaments in Miami [Images] and Beijing [Images] after her comeback last year but also endured the disappointment of being beaten in the finals of Wimbledon and the season-ending WTA Championships, losing to Russian teenager Maria Sharapova [Images] both times.

Williams said those experiences had made her more determined to battle back and that she drew strength from them in the final.

"It means a lot to me. I went to a few finals last year and I went so close and didn't win, so I really didn't want it to happen again," she said.

Davenport, the 2000 champion, raced to a 4-0 lead in the first set after only 11 minutes, with Williams leaving the court for treatment when she trailed 4-1.

The former world number one returned to court and ground her way back before a pivotal fifth game in the second set.

Williams gamely held off six break points against her serve in that game before slamming a service winner to hold for 3-2 in what proved to be the turning point of the match.

"I kept thinking to myself 'I'm not losing this game. I don't care if my arm falls off, I'm not losing this game'. And I guess that's what happened," Williams said.

"I didn't want to lose that particular game because it would have given her a lot of momentum, and a lot of confidence."

Williams then won nine straight games from the seventh game of the second set to shut a crumbling Davenport out of the final.

"Eventually I was able to come back, thank goodness," Williams said.

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