At this time three years ago, Jennifer Brady was en route to reaching her first Grand Slam final at the Australian Open. But shortly after reaching her career-high ranking of No.13 a month later, the American was sidelined for nearly two full years with a combination of foot and knee injuries.

Though she briefly returned to tennis in the summer of last year, the 28-year-old now says she's being forced into another extended hiatus.

The American revealed on social media on Thursday that she suffered a setback in the offseason, and will soon undergo another knee surgery. While she gave no timetable for a comeback, the former World No.13 said her recovery and rehabilitation process will be "extensive." 

"While it hasn't been easy dealing with injuries and taking time off at the peak of my tennis career, I was grateful and happy to be back competing and playing at the highest level during the US Open swing and end of last year," Brady wrote on Instagram.

"I never expected this life to be easy -- playing professional sports at the highest level is difficult on the mind and the body, but I enjoy every moment of it and wouldn't change a single thing."

Brady played six events last year in her brief comeback, highlighted by a third-round effort at the US Open -- where she reached the semifinals in 2020.

In the interim, Brady says, she's re-enrolling at UCLA -- where she studied for two years in 2013-15 while playing for legendary head coach Stella Sampras-Webster (sister of 14-time men's singles Grand Slam champion Pete Sampras) on the school's women's tennis team before turning professional. While she resumes her undergraduate studies, she says she plans to serve on Sampras Webster's staff as an assistant coach.

"I'm bummed not to be competing during this time, but I am very excited to be a part of the UCLA tennis team again," Brady wrote.

Several of Brady's peers -- including fellow Americans Coco Gauff and Sloane Stephens, and former Grand Slam champion Samantha Stosur -- were among those to offer her encouragement in the comments of her post. 

"You’ll be back whipping that fear hand in no time at all," Stephens wrote, referencing Brady's chief groundstroke weapon, her forehand. "Proud of you for always fighting Jen!"

"Sending you love," Gauff added. "Hope to see you back soon."