With title favorites including world No 1 Serena Williams withdrawing due to injuries, this year's China Open has become an even fiercer battle for the rest to fight to unseat the top stars.

Serbian star Ana Ivanovic is one of those ambitious players expecting to close the year with an excellent performance at the season's last Premier Mandatory tournament on the WTA Tour in Beijing.

"I am glad to be back here, I had great memories here last year (of reaching the semifinals). Honestly speaking, the field is still big, tough and strong (after some high-ranking players' quit)," the world No 9 said in her pre-tournament press conference on Friday.

As one of four WTA PM events, all the world's top 50 female players were supposed to compete in Beijing for 1,000 ranking points and the total of more than $4.7 million prize money.

However, a glittering list of stars including 21-time major winner Williams, tournament defending champion Maria Sharapova and former world No 1 Victoria Azarenka of Belarus all announced they would quit from the tournament citing health issues, casting a shadow on the biggest tennis event in China.

The lack of star power might disappoint the fans but has provided a golden opportunity for the rest of the contenders.

"I had a really good memory last year in Asia especially winning in Tokyo and entering the semis here. I really hope I can have the same success as last year. I really had some good matches last week, I hope I can keep that level up and keep improving," said the 27-year-old Serb.

Seeded in the second half of the 64-player main draw tournament, Ivanovic will potentially meet former world No 1 Venus Williams in a tough second-round clash after facing off Australian wild carder Casey Dellacqua in the opening round.

Romanian world No 2 Simona Halep, the highest-ranking contender in the field, echoed Ivanovic's sentiment, stressing it's more important to focus on her own performance.

"Of course, you can think it's an opportunity to play your best, but everyone is playing well here. This tournament is open, it's very important for everyone so I can say that you know maybe I have the chance but it's too far to think about that."

Placed in the first quarter of the main draw, Halep won't meet with much of a challenge until possibly squaring off against Italian veteran and US Open finalist Roberta Vinci in the third round.

Four Chinese players —Wang Qiang, Zhang Shuai and Han Xinyun as well as Zheng Saisai — entered the main draw as wild card holders and are expected to deliver breakthroughs in front of home crowds.