Ralph Macchio: Dancing with the cyst

May 9, 2011 at 7:32 p.m. ET

Ralph Macchio has been a tough competitor on Dancing With the Stars, however, he is battling a painful cyst on his knee that is threatening to steal the dancing trophy away from him. Can he and his partner Karina Smirnoff karate chop their way through the performance tonight?

Dancing with a limp? Ralph Macchio has been unable to rehearse for his Dancing With the Stars performance much of this week because of a painful Baker's cyst on the back of his knee.

Ralph Macchio and Karina Smirnoff

"Been down this wk dealing w/some serious pain management, but as someone once said 'nothing's gonna ever keep me down,'" he tweeted. "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! 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!"

His dancing pro partner Karina tweeted pleas for sympathy as they prepare for their cha cha tonight, saying, "We r doing everything we can to be ok 4 tonite. 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."

ABC has confirmed that Macchio is dancing -- as of now. "We believe he will be dancing tonight." That doesn't sound too reassuring.

Ralph and Karina are up against Chelsea and Mark, Hines and Kym, Romeo and Chelsie and Kirstie and Maks.

Check out Dancing With the Stars on Monday and Tuesdays 8 p.m. central time.