Serena Williams, World's No.1 Tennis Superstar, Pulls Back From Hopman Cup Opener Due To Knee Injury

Serena Williams, the world's No.1 tennis superstar, got off to a stammering start this new season after she pulled back from Monday's Hopman Cup opener because of a minor knee injury.

According to CNN, Williams was disappointed that she was not able to made to Perth because of her injury. Her cartilage injury has not fully healed and Williams also sustained bone bruises that could lead to a stress fracture if she continued playing.

Patrick Mouratoglou, Williams' mentor, said the American star is dealing with same pain that stopped Rafael Nadal's career before. With Williams current health condition, her career would have been in danger had she continued playing. 

"Unfortunately due to inflammation in my knee, I need to rest and am confident to be out there against Aussie Gold tomorrow evening," Williams said.

According to Tennis, Williams trained for the season-opener with Elina Svitolina of Ukraine. Williams spot was given to Vicky Duval

Paul Kilderry, the tournament director, shared that Williams was initially unwilling to pull out from the match until she tested her knee injury on Monday and felt the pain again while practicing. 

After her victory in the Australian Open, French Open and Wimbledon in 2015, Williams barely missed finishing a season Grand Slam when she lost to Roberta Vinci in the elimination rounds of the U.S. Open. 

The Hopman Cup is an annual group tournament participated by eight countries.