BALI (Indonesia) (Reuters) - Ana Ivanovic celebrated her 24th birthday by successfully defending her Tournament of Champions title with a comfortable 6-3 6-0 victory over Spains Anabel Medina Garrigues on Sunday. The victory was the Serbs 11th singles title but first since winning the event last year. Her previous best results in 2011 were achieved with semi-final appearances in Birmingham and Carlsbad. The Spaniard was seeking her third title of the season following victories in Estoril and Palermo, and had enjoyed an easier route to the final after her previous two opponents this week retired from their matches. Marion Bartoli suffered an ankle injury and quit after holding two match points and Sabine Lisicki failed to complete the third set of their semi-final due to a back problem. I feel great, Ivanovic told reporters. I think I played an impeccable match today. I didnt do much wrong and really stayed so focused and even sat at her chair (at a change of ends). Ivanovic, who was granted a wild card into the tournament, won all three of her matches in straight sets and did not face a break point in the final. Although Medina Garrigues defended well and engaged her Serbian opponent in many long rallies, it was Ivanovic who always found the killer shot, producing a number of spectacular winners. Ivanovic broke just once in the first set, to lead 2-0, but she also held four break points to lead 4-0 before Medina Garrigues managed to haul herself into the match. The second set was a rout, however, as Ivanovic surrendered just seven points on her way to her convincing victory. Remarkably, Ivanovic went into the match concerned about her ability to perform. My shoulder was actually scary, Ivanovic admitted. Yesterday it started to feel really sore. I did some autographs after the match and I couldnt even sign. I really tried to keep points short and take pace off my serve and it really worked well. Im very proud of the way I played and the way I handled myself. Medina Garrigues felt she was helpless as Ivanovic played at such a high level, and believes her opponent is capable of regaining the number one ranking she held briefly in 2008. I dont feel good about the way I played today, but Ana was playing so good I couldnt do too much, said Medina Garrigues. She didnt feel the pressure and was playing good, solid. I think she can be number one again. She has unbelievable tennis. Its difficult, but she was already number one. Its going to be tough but she has the game, the technique and the physical strength. Following a three-year run in Bali, the tournament will move to Sofia, Bulgaria for three more years from 2012.