Serena Williams was pulled out of the mixed teams Hopman Cup because of a knee injury on Wednesday, Jan. 6, a few weeks before the Australian Open.

Williams retires from her match against Australian Jarmila Wolfe after hobbling through a set-and-half in Perth due to an inflammation in her knee. The 34-year-old American tennis star decided she could not go on the following day, as reported by Reuters.

She declined to rule out going back to the court for the United States' match againt the Czech Republic, although she officially ended that on Wednesday. She's hoping that the injury will not spoil her plans for the Australian Open on Jan. 18.

"I have some knee inflammation that's going away very slowly. It's going, it just needs a little more time," Serena said after retiring against Wolfe. "Maybe a day off or two will really make the world of difference. It's not even a bump -- just a really minor thing in the road and I'll fly over it."

According to USA Today, Vicky Duval will be Williams's replacement in the US team for the last Group A match versus the Czech Republic on Thursday. The team is 0-2 and cannot get into the final of the international mixed team competition in Perth Arena.

Williams won the 2015 Australian Open, French Open and Wimbledon and got within two victories of a season Grand Slam before losing in the U.S. Open semifinals. "The whole year was great," Williams reflected. "But it was also physically very, very difficult. I'm looking forward to this year and making the best of it." 

"I'm just taking it a day at a time still. I'm not making any decisions now," she said when she was asked whether she has decided to play at the 2016 Australian Open.

Williams is expected travel to Melbourne and continue her preparations for the Australian Open.