Bad news for Derek Hough.
After injuring himself rehearsing for the 10th Anniversary Dancing with the Stars special on Monday night, the 29-year-old dancer has been diagnosed with a broken toe on his right foot, sprains on both the inside and outside of his left ankle, and a bone bruise on the same ankle, his rep tells ET. Derek will have to remain in Los Angeles this week to rehab his injuries, while his understudy will be filling in for him for the New York Spring Spectacular show in NYC.
But will his injuries force him to drop out of DWTS?
For now it remains unclear if Derek will be able to perform on Monday's episode, but his partner Nastia Liukin will train in Los Angeles this week with pro-dancer Sasha Farber to prepare for the live show.
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Though don't count out Derek just yet. He displayed his determined attitude on his Instagram on Tuesday, writing, "Your setback is a platform for your comeback."
Derek's close friend and fellow DWTS pro Mark Ballas -- who spent most of the night with him in the ER -- talked to ET on Tuesday, and gave us an update on his condition.
"It was just ironic that it was two feet," Mark told ET, referring to Derek's now deleted Instagram post showing two bandaged feet. "But fingers crossed that it's not gonna be as bad as we thought. The X-rays came out good I believe."
Mark says Derek is remaining positive despite his unexpected injury.
"Derek's always in good spirits," he stressed. "Derek's always up, always positive, always supportive of everybody -- that's why it hurts when you see someone that happy, and someone so positive and great go down."
Mark remains optimistic about Derek's return to the hit ABC show.
"He'll come back harder, better, faster, stronger," he said. "He'll be back."
NEWS: Inside Derek Hough's 'DWTS' Injury -- What Really Landed Him in the ER
Find out more on Derek's injury -- which according to his former DWTS partner Maria Menounos, he got when he smashed his foot on a piece of equipment then fell down the stairs -- by watching the video below.