(CNN) -- Victoria Azarenka might be giving up her spot as World No.1 but the Belarusian showed successor Serena Williams that she's ready to fight to get it back.
Azarenka avenged the loss of top spot to Williams by defeating the U.S. star 7-6 2-6 6-3 in the final of the Qatar Open in Doha Sunday.
Williams, 31, will become the oldest woman to ever hold the No.1 ranking in the history of the game when she takes over Monday.
But she failed to follow up her impressive semifinal win over Maria Sharapova following an error strewn performance.
Instead, Azarenka, who successfully defended her Australian Open title last month, ended a nine-match losing streak against Williams to record just her second win in 13 attempts over her opponent.
Leading 5-2 in the first set, the outgoing World No.1 allowed Williams back into the game with the American racing into a 6-5 lead.
Williams had set point but failed to take advantage and Azarenka ensured her opponent paid the penalty by taking the opener on a tie-break.
Williams hit back in the second, taking it 6-2, but she was unable to sustain her form and faltered in the third and decisive set.
"I can't say that I'm depressed like I am whenever I lose.," Williams told reporters. "I'm definitely not happy, but I'm number one."
"It was such a long journey, and after winning Wimbledon and the US Open and the (season-ending) Championships, I thought, I just don't think I can win anymore. I don't know what it takes to be number one.
"It was a good match overall. Victoria played really well, and did a great job."
Azarenka believes that her recovery from losing a one-sided second set was key to her success.
She told reporters: "I just wanted to fight and give it my best, and give myself every opportunity.
"I started at love-30 down and it was 'you have to keep it together and pull it around'. Serena was on a roll.
"I knew she would bring her A game, and I was really glad I could stay tough and focused."
Azarenka, who went 26-0 before losing at the quarterfinals in Miami last year, is now 14-0 in 2013.