Serena Williams announcing her withdrawal from her last two scheduled stops of 2015, Beijing and Singapore.

Twenty-one-time Grand Slam champion and World No.1 Serena Williams has had to call it a year, withdrawing from her last two scheduled tournaments of the 2015 season, the China Open in Beijing and BNP Paribas WTA Finals Singapore presented by SC Global, to address her health and to heal.

Williams has had one of the most successful seasons of her career this year, highlighted by winning three Grand Slam titles - the Australian Open, French Open and Wimbledon - to bring her career haul to 21, and already securing the WTA Year-End World No.1 Singles Ranking, presented by Dubai Duty Free, her third straight year finishing on top of the WTA Rankings, and her fifth season overall. But all of the injuries she's had to overcome throughout the year finally caught up with her. 

 "It's no secret I've played injured most of the year - whether it was my elbow, my knee, or, in the final moments after a certain match in Flushing, my heart," Williams said, referring to her semifinal loss to Roberta Vinci at the US Open, where she was two wins away from the Calendar Year Grand Slam. 
 "I want to compete as well as I can, as long as I can. So I'm taking a proactive step and withdrawing from tournaments in Beijing and Singapore to properly address my health and take the time to heal." Williams hopes to get back on the court during the off-season. At the Australian Open in January she will be going for her 22nd Grand Slam title, which would tie Steffi Graf for most in the Open Era. "This is a very difficult decision, but one ultimately made because of the love of the game," Williams commented. "I plan to return to practicing and participating in exhibition matches later this year. And when I do, l will focus and focus and focus so I can continue my journey in this beautiful game."