Blame Len Goodman!

Derek Hough was personally offended by the judge’s attacks two weeks in a row, but he's not going to let it get to three. For more serious reasons, Derek said he plans to sit out Dancing With the Stars All-Stars Week 7. It's not really because of Len — it's an inflamed injury.

Monday night, Derek told On the Red Carpet he has a bulging disc in his vertebrae that became inflamed that day. "I've had it for a couple years," he explained to Zap2it, "but once it flares up — like it did today — it sort of immobilizes me."

Guess he really meant it! During Tuesday’s Week 6 Results Show, Derek told Brooke Burke-Charvet he would be stepping out next week, due to his injury. "Just to take precaution I think next week I'm going to have to step out a little bit and have Mr. MB — Mark Ballas step in with his previous partner."

Wow. Well, the good news is Mark will be able to dance with Shawn Johnsonhis winning Season 8 partner. But no Derek? Eek. Get well soon, man!

Catch a new episode of Dancing With the Stars Season 15: All-Stars on Monday, November 5 at 8 p.m. ET/PT on ABC.

Sources: On the Red Carpet, Zap2it

Gina Carbone is a contributing writer at Wetpaint Entertainment. Follow her on Twitter @ginacarbone.

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