Victoria Azarenka couldn't defend her place at the top of womens' tennis this week, but she wasn't prepared to lose her Qatar Total Open title at the same time.

The outgoing world number one showed why she's still worthy of the top ranking with a gutsy three-set victory over Serena Williams in Doha that promised much and delivered even more.

"I won't say I didn't feel pressure, I was just really into the match and really focused on what I had to do," said Azarenka. "Near the end she saved a match point with a good serve - that's what you normally expect to get from Serena when she's in trouble - a bullet. But it wasn't a big deal, really - I just had to keep my composure and make another opportunity and create another match point."

Williams, who cemented her position as world number one with her emotional quarter final win over Petra Kvitova on Friday, threw everything she had into Sunday's final but couldn't hold off Azarenka's final set flourish that snapped a painful nine game losing streak for the Belarusian against the legendary Williams.

The tennis was top class throughout, however, and bodes well for both the sport and the burgeoning rival between the veteran Williams and the 23-year old Azarenka, who took the opening set in a thrilling 7-6(6) tie break.

Williams, who seemed troubled by the cold and windy conditions in the opener, fought back hard in the second set, winning crucial points and gaining an early break advantage before going on to win the set comfortably 6-2.

Azarenka could have folded quickly in the third after the disappointing loss, and was indeed down 0-30 in her opening service game, but she dug deep to both hold that game and break the 15 time Grand Slam Champion's serve in the next to take a commanding 2-0 lead in the decider.

Another break gave the defending champion a 5-2 lead even as Williams hammered away from the baseline with an array of powerful ground strokes.

But even with the scar tissue of her disappointing loss to Williams in the US Open final last year still affecting her game at times, the rock-solid Azarenka refused to yield.

And even after blowing a match point at 5-2, she gathered herself for a impressive service game that took the final set and closed out the match and collect her 16th career WTA title.

Still, there was some poetic justification in the outcome of such a high-quality match: Azarenka can righty take joy in her title defence - he second of the year in a so-far unbeaten season - while exorcising the ghost of nine consecutive defeats to the American.

Williams, on the other hand, can't help but feel pleased to retrieve her spot at the top of the WTA rakings for the sixth time - and after a two year hiatus - while at the same time lamenting some of the mistakes - 48 unforced errors in total - that help her rival win today.

"On my end it probably wasn't the best quality - I made so many errors. It was just weird," she said. "My serve, oh my gosh - it was just one of those days. I'm having too many of those days. I've got to cut them out. This whole week I just don't think I played my best tennis. But I was fighting every match. I was really excited to make it to the final with the game I was playing all week.

"I can't play that quality game against a top player like Victoria. I have to be able to pick up my game, and I wasn't able to do that today. I stayed at a 2 out of 10, and I really can't play that low."

In the end, then, despite the score line, it was honours even for the two great champions after a scintillating week of tennis.