Sydney (Reuters) - US Open finalist Caroline Wozniacki and former world number one Jelena Jankovic joined a growing list of early exits at the Sydney International on Monday. Frenchman Gael Monfils and Russian Vera Zvonareva also bowed out of the combined ATP-WTA event, succumbing to injury just a week before the start of the Australian Open in Melbourne. Monfils pulled out before hitting a ball at the Olympic Tennis Centre due to a shoulder injury suffered last week at Brisbane. "I think I have an inflammation... it's getting worse and worse," the Frenchman said. "If you keep playing on it, it's going to turn into something chronic I think, so I need to take a few days off." Zvonareva, who made her first Grand Slam semi-final last year in Australia, was limping out of her first round with compatriot Elena Vesnina with a recurring ankle problem. Zvonareva underwent surgery in November last year, but re-injured it again while playing in an exhibition in Hong Kong last week. She thought she had recovered enough to play in Sydney but retired with the scores locked at 3-3 in the first set. "I had to hit a backhand and just hurt my ankle again," she said. "I did my best to keep playing but it was too painful to finish the match. I had to stop." Poor preparation due to jet-lag saw Wozniacki beaten by China's Li Na 2-6 6-3 6-2. "I don’t know. I didn’t play my best game today," the Dane said. "I arrived yesterday from Hong Kong and maybe it’s not the best preparation I could have had." Belarusian Victoria Azarenka, who also played in Hong Kong, was the only seeded woman to survive, coming from behind to beat Germany's Sabine Lisicki 3-6 6-0 7-5. Jankovic, who has slipped to eighth in the world rankings after being inside the top 12 twelve months ago, lost her opening match 5-7 6-1 7-5 to Hungary's Agnes Szavay. The Serb hasn't made it past the fourth round of any of the Grand Slam tournaments last year and her early exit in Sydney leaves her short practice heading towards Melbourne. "It was my first match of the season and I was a bit nervous," she said. "I really did my best (but) I wasn't playing well. I wasn't hitting the ball like I wanted and I wasn't serving well either." I just have to clean up some things in my game and do better next time." Top-seeded American Serena Williams plays her first match of the year against Spain's Maria Jose Martinez Sanchez on Tuesday. (Compiled by John O'Brien)