American tennis star Serena Williams' withdrawal from her next two Asian tournaments has cast a question mark over her participation at the season-ending WTA Finals in Singapore next month.
The 34-year-old world No. 2 yesterday pulled out of next week's Wuhan Open as well as the Oct 1-9 China Open in Beijing, citing a right shoulder injury.
Williams announced her withdrawal just hours before the Wuhan Open draw ceremony took place.
The 22-time Grand Slam singles winner said in a statement on the Women's Tennis Association (WTA) website: "I have been practising and playing but my shoulder is still not fit for tournament play.
"I am disappointed that I will not be able to compete at the Wuhan Open or the China Open due to continuing issues with my right shoulder."
It was the same inflamed shoulder that has troubled her in the latter half of this season, which has also seen her skip the Rogers Cup in July and the Cincinnati Open in August.
She has played in just eight events this year, including the four Grand Slams and the Olympic Games.
The two tournaments in China - Wuhan (premier) and Beijing (premier mandatory) - are key stops in the WTA calendar, offering the most ranking points before the Oct 23-30 WTA Finals presented by SC Global in Singapore.
With the season finale less than a month away, Williams is aiming to get fit for the WTA Finals, an event she has won five times.
She said: "I am focused on getting ready to compete at the WTA Finals in Singapore."
Williams and recently-crowned world No. 1 Angelique Kerber are the first two singles players who have qualified for the WTA Finals, which will feature the eight best singles players and doubles pairs of this season.
To drum up the hype ahead of the Finals, a tennis-themed festival called 'City Serves Up Tennis!' will be held from Oct 7-9 at Suntec City.
Organised by the Singapore Tourism Board, the public can take part in a tennis-themed mass workout session, watch a live screening of the China Open and take a photo with a wax figure of Williams.
She hoisted the Billie Jean King trophy on her last appearance at the Singapore Indoor Stadium in 2014 but skipped last year's edition.
Her fans are hoping that they will not be disappointed for a second year running.
Methodist Girls' School tennis player Tamara Tan, 16, remembered standing metres away from Williams in 2014.
The Secondary 4 student said: "Watching her was so mesmerising. She's the best player ever and if she misses such an important tournament, it will be like a (men's tennis) event without Roger Federer.
"I hope that she can come this year."