DWTS Pro Lindsay Arnold Has Injured Her Knee and May Be Unable to Compete

Dancing With the Stars pro Lindsay Arnold has injured her knee during rehearsals — and it remains unclear whether or not she’ll be able to perform with celebrity partner Jordan Fisher on Monday’s show.

“Lindsay injured her knee during camera blocking rehearsal Sunday morning while working on a number with the troupe,” a DWTS source told PEOPLE, who explains that the girls from the troupe are standing in for her at rehearsal and pro Sharna Burgess, who was eliminated alongside her partner Derek Fisher earlier this season, is learning her routines in case Arnold is too injured to perform.

“Lindsay is hopeful she’ll be cleared to dance tomorrow but it will likely be touch and go until showtime Monday,” the DWTS source continued.

“I was practicing the pro number and I literally just stepped up onto a stair and it felt like my whole leg gave out and stopped working and I thought it was just a one-time thing and then it happened a couple more times, just doing simple things,” she said, tearing up during physical therapy treatment.

Continued Arnold, “It’s frustrating because it’s the semi finals and I want to dance it with Jordan, and I just hope this doesn’t stop me from doing that.”

Lindsay Arnold (left) and Jordan Fisher
Lindsay Arnold (left) and Jordan Fisher

Arnold is the only pro left in the competition who has never won the Mirrorball Trophy, but she and her partner are currently at the top of the DWTS leaderboard.

If Arnold does return to the ballroom on Monday, she and Fisher will be dancing both a new routine and an iconic dance from DWTS history. In addition to the new dance, the couple is set to perform a jive to “Proud Mary” by Tina Turner which was originally performed in Season 22 by mixed martial artist Paige VanZant and Mark Ballas.

PEOPLE’s special issue, 25 Seasons of Dancing with the Stars, is on stands now.

The pro isn’t the only competitor from the show to get injured this season — violinist Lindsey Stirling suffered a rib injury two weeks ago but danced through the pain and has remained a serious contender for the show’s top prize.

“She’s doing better,” Stirling’s partner Mark Ballas told reporters after the show at the time. “She wanted to be here tonight [to talk to press], but I told her she needed to go rest and put ice on her ribs. I was with her yesterday when it happened. We took the X-ray — I was really nervous at that point because if there had been a break or a fracture, that would have been a huge problem. There’s no break or fracture. They call it a floating rib.”

He added, “I know that the muscles between the ribs are really painful — it’s the worst. It’s going to take a minute. We’re going to ice it, but luckily she’s in a state where she can continue [in the competition].”

Dancing with the Stars airs Mondays (8 p.m. ET) on ABC.