Kimiko Date-Krumm, 45, has decided to undergo left knee surgery, and is unsure whether she can return to the tour.

The former world No. 4 from Japan told Mainichi.jp that she has been injured at times during the year and does not know how well her leg will heal.

In singles competition, Date-Krumm played 24 tournaments in 2015, but did not go deep at any event. She began 2015 ranked No. 102, and fell to No. 193 after exiting in the first round of qualifying at the 2016 Australian Open three weeks ago.

"I've decided to have an endoscope surgery on my left-knee meniscus,” Date-Krumm said. “I had an MRI a day after returning from the Australian Open, and the part where [there] was a crack now [has] a rupture. I thought about the life as an athlete and after. I don’t know when I can return, but I’ve decided on the unknown of having an operation and the ensuing rehab, believing I can stand on the court again one day."