Serena Williams has described winning her third WTA Tour Championships as 'achieving a dream'.

Williams crushed Maria Sharapova in straight sets to claim the season-ending title in dominant fashion, capping off a strong comeback year.

The American admitted that she was surprised to find a passionate crowd in Istanbul and was delighted with the support.

"It feels great to have achieved my dream," Williams said.

"The Turkish crowd were fantastic. I have never seen so many signs with my name on them before.

"To come back after being in the hospital, I feel so happy whether I win or lose, its awesome."

The 31-year-old has enjoyed a remarkable return to form in 2012, winning at Wimbledon and the US Open plus earning an Olympic Gold medal.