By Lynette Rice
Updated August 31, 2015 at 12:00 PM EDT
Credit: Craig Sjodin/ABC via Getty Images

A leg injury has forced pro Peta Murgatroyd to skip season 21 of Dancing With the Stars.

People is reporting that Murgatroyd, who was partnered with singer/songwriter Andy Grammer for the new season beginning Sept. 14, tore four ligaments and has a floating piece of bone at the bank of her ankle. “My doctor said I needed surgery and I knew I needed to put my health first if I want to keep dancing on the show into my 30s,” she told the magazine.

Murgatroyd spent the last three months performing on the live DWTS tour but sought out an orthopedic surgeon when “something was not right.” She will undergo surgery in September.

“It was awful telling Andy,” she told People. “He had specifically asked to be partnered with me and I felt like I was letting him down,” she says. “But he understood and has been a great guy about it.”

All the celebrities for the new season will be announced Wednesday on Good Morning America.