NEW YORK (AFP) - Just 15 months after winning the French Open and becoming world number one, 11th-seeded Ana Ivanovic made her first opening-round exit in 20 Grand Slam appearances on Tuesday at the US Open. The 21-year-old Serbian beauty squandered a match point and was ousted by Ukranian Kateryna Bondarenko 2-6, 6-3, 7-6 (9/7) in a matchup of injured rivals trying to outlast each other. "Obviously it hurts," Ivanovic said. "I created a lot of chances for myself and I'm really disappointed that I made a few mistakes in the important moments and my forehand let me down on a few occasions. "I played great, set myself up and made the mistake in the net every time. It's a little frustrating."Ivanovic reached the fourth round at Wimbledon and the French Open and the third round at the Australian Open after fighting back from a shoulder injury, results that will leave her pondering a lost year in her career. "It's very disappointing. It hurts. I'm sure I will have sleepless nights," she said. "But I have to accept it and try to put this year behind me and try to learn from it. "As much as it hurts and was disappointing, I learned a lot about myself and what I have to do in order to become a better player. Ivanovic's instincts and thoughts are at war with each other when she is on the court and her results has slipped as a consequence. "When I follow my instincts, I play great," Ivanovic said. "Then I think I can make other shots and I feel maybe I should go different direction. That's when bad shot selection comes. That's just mind and emotions."Ivanovic has lost the rhythm between the key elements of her game and that has weakened her confidence. "My mind and my body and everything, it's not on the same level," she said. "But I think it has also to do with the confidence, because many times when I'm in a position, I just don't trust myself like I did before."I've been thinking about everything too much and trying to address lots of issues with my game." At the moment I feel like I have a plan in place and I know what I have to do in each area. "But just at the moment I think it's a little disbalanced. My fitness is at one level, mind at another, my game is at another level. I think these all these things have to marry to get into the right direction and have to fit." Ivanovic traces the start of her troubles to her brightest moment, the 2008 French Open title. When she was unable to match that level, she began to search for solutions to problems that were only in her mind. "When I started to not have the results that I expected, that's when my mind games play. That's when I started to think and analyze everything that has been happening and trying to fix something that maybe wasn't broken," Ivanovic said. "I tried to go different directions and tried to search for it elsewhere and that's when I feel like I went on a little, forcing, trying to change technique and some kind of areas of my game that were not necessary to do so. "So now I'm really back to basics. It feels a lot better. I'm practicing good. I'm really happy. I need some time and hard work."