Macchio himself first sounded the alarms this morning, tweeting that he suffered a painful ruptured cyst on the back of his knee that rendered him and partner Karina Smirnoff unable to rehearse for a large portion of the week.
Not what you want to have happen ever, let alone entering into the final few weeks of the competition.
"Been down this wk dealing w/some serious pain management, but as someone once said 'nothing's gonna ever keep me down' :-)," he wrote just hours ahead of tonight's performance show.
"Have missed days of rehearsal this week. Had a ruptured cyst back of my knee causing acute pain. Hoping to be able to perform tonight!" he went on. "Will be rough around the edges w/o rehearsal time. But performing with @Karina_Smirnoff for u guys is the hi-light of every week. Hangin in!"
The operative word there, of course, being in. Though now may be the time to move up his long-promised, finale-saving Karate Kid moves. If ever there was a time to break out the crane, surely it's now.
Partner Karina confirmed the injury, specifying that it was a Baker's cyst, and that the fluid build-up came with severe inflammation and tendinitis.
"We r doing everything we can to be ok 4 tonite," she tweeted. "We lost 4 days of rehearsals. But I couldn't be more proud of @ralphmacchio & his will and desire to continue through pain. Please pray 4 us."
Meanwhile, a spokeswoman for ABC confirmed to E! News that, as of now, Ralph is not yet out of the competition.
"We believe he will be dancing tonight," the rep said.
As long as no one sweeps the leg, this could be his moment. Good luck!