'Extreme Weight Loss' Gets a Very Special Guest


Extreme Makeover: Weigh Loss Edition's Chris Powell is once again changing lives this season, and in this exclusive clip, he has a bit of help joining him -- Super Bowl and Dancing with the Stars champ Donald Driver!

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Powell enlists Driver to ride a challenging 43-mile relay race with 23-year-old Ryan -- who lost his left arm in a car accident -- and his family, who happen to all be devoted Green Bay Packers fans.

"I've watched your story and it's truly touching," Driver says. "I'm just glad you allowed me to be a part of this."

But things don't exactly go smoothly, as Ryan suffers a potentially devastating setback due to fatigue.

Video: 'Extreme Makeover' Contestant Drops 157 Pounds

Check out the clip to see the tense moment go down.

Ryan's inspiring Extreme Weight Loss episode airs June 25, at 8 p.m. on ABC.