Serena Williams has announced her plans to retire from tennis after the US Open. 

The 23-time Grand Slam champion has dominated the sport for nearly 20 years and is the most successful female player in the Open Era. 

But after facing a combination of injuries and the birth of her first child, Williams has been forced to stay away from the court for some time. 

Now the Tennis star has shared today that she plans to retire from the sport, saying the news on Instagram, promoting the athlete's Vogue September cover.

Hinting that one of her main reasons for retiring from the sport that she has professionally played since she was 14 years old is motherhood.

Williams wrote: "There comes a time in life when we have to decide to move in a different direction.

"That time is always hard when you love something so much. My goodness do I enjoy tennis.

"But now, the countdown has begun. I have to focus on being a mom, my spiritual goals and finally discovering a different, but just exciting Serena.

"I'm gonna relish these next few weeks."

The tennis champion shared more reasons behind her decision in her interview with Vogue for the September issue. 

Saying: "I’m turning 41 this month, and something’s got to give,’ Williams said.

She added: "I have never liked the word retirement. It doesn’t feel like a modern word to me. I’ve been thinking of this as a transition, but I want to be sensitive about how I use that word, which means something very specific and important to a community of people.

"Maybe the best word to describe what I’m up to is evolution."

Williams added that she's not sure what's next for her and that she isn't ready for it to be over.

However, she did admit that she is excited for whatever comes next.