Djokovic holds key for Ivanovic in Serena clash

Ana Ivanovic believes Serb compatriot Novak Djokovic could tip the balance in her favour when she takes on red-hot title favourite Serena Williams for a place in the US Open semi-finals. Ivanovic has never beaten 14-time Grand Slam title winner Williams in three meetings, failing even to win a set, with two of those defeats coming in New York in 2006 and 2011. But having ended her four-year wait to reach a first Grand Slam quarter-final since she made the same stage on the way to her one and only major triumph at the French Open in 2008, the 24-year-old is desperate not to waste her opportunity. And that's why Djokovic, the defending men's champion in New York and reigning Australian Open champion, could have a crucial role to play. "We speak a lot. He had a great year last year. He's a dear friend of mine. It's great to get some experience and advice from someone like him," said Ivanovic, who made the quarter-finals with a 6-0, 6-4 win over Tsvetana Pironkova of Bulgaria. "We spoke a lot at the Olympics and in Wimbledon, and it made me realize how important it is to have someone there who is going to take care of the body and recovery and all these little things, because they are the small parts that make the difference." Ivanovic has never previously made the US Open last eight, having fallen at the fourth-round stage on three previous occasions. The former world number one, now ranked 13 in the world, has made the last eight by not having to face a seeded opponent having seen scheduled fourth-round rival Caroline Wozniacki lose in the first round. Wozniacki paid the price for continuing to play in New Haven on the eve of the US Open despite picking up a knee injury. Ivanovic, for her part, skipped the Cincinnati warm-up event to rest her injured foot. "I was really unfortunate with my foot injury before the tournament, so if someone would have told me I would be in this position, you know, I'd be like, 'OK, that's nice. Thank you,'" said the permanently cheerful Serb. "I have been working really hard on recovery and on court, as well. It's kind of a reward. I want to enjoy that process. I still have lot of things to think about this year." Williams, the three-time champion, will give her plenty to ponder when they meet in Wednesday's quarter-finals. The 30-year-old American reached a 10th US open quarter-final on Monday with a 6-0, 6-0 rout of hapless Czech Andrea Hlavackova. She has dropped just 12 games in four matches at this year's tournament. "Last year when I played her here, I thought I had some chances in the second set," said Ivanovic. "But it's always tough. She's obviously a great player and she's been playing the best out of all the girls on tour at the moment. "Her serve is definitely her strength. I really have to be sharp from the first moment on and stay aggressive and stay in the moment. I need to try and enjoy the challenge. It would be great opportunity for me."