Former UFC interim heavyweight champion Shane Carwin is set to fight once again.

The knockout specialist last fought over five years ago in the Octagon in a losing effort against Junior dos Santos at UFC 131. Carwin announced his retirement from mixed martial arts shortly after his loss to dos Santos with injuries hindering him from competing at his best.

Now, Carwin is set to return to competition as the RIZIN Fighting Federation announced the UFC veteran will compete in the second round of the open weight World Grand Prix tournament on December 29 in Saitama, Japan. Although no opponent has been named for Carwin yet, many fans are surely excited to see the heavyweight compete once again.

RIZIN tweeted early Thursday morning, “The last fighter for the tournament is announced! SHANE CARWIN 👊🏻”

Carwin tweeted a few days ago a hint of fighting for RIZIN. Carwin posted a photo of an XL RIZIN MMA glove and said, “Hey [Rizin FF] you are going to need bigger gloves, these do not fit, not even close.”

Carwin also revealed some very interesting information to a fan that said, “would love to see you fight Fedor.” Carwin replied and said, “I accepted that fight two weeks ago. Would be an honor. It is up to him.”

Shane Carwin is a former NCAA Division 2 wrestling champion and holds a 12-2 professional MMA record with big wins over former UFC heavyweight champion Frank Mir and the powerful Gabriel Gonzaga. Carwin’s two losses were his last two professional fights, falling to Brock Lesnar by an arm-triangle choke in the second round of their championship fight at UFC 116 where he nearly took Lesnar out in the first round and the decision loss to Junior dos Santos.

Who do you want to see Shane Carwin fight in his comeback on December 29 in Japan? Sound off in the comments!