EXCLUSIVE: Nick Jonas Strips Down in This 'Kingdom' Sneak Peek and Prepares For the Fight of His Life!

Note to self: Don't mess with Nick Jonas!

Note to self: Don't mess with Nick Jonas!

The "Close" singer is stripping down and stepping back into the cage in this week's all-new episode of Kingdom, but don't let his sexy muscles and knockout bod distract you -- his punch is lethal.

Jonas, as his kickass MMA-fighting character, Nate Kulina, is gearing up for the fight of his life in Wednesday's episode "Halos" -- and only ET has your exclusive first look at the heart-pounding moment!

MORE: Nick Jonas Talks Playing A Gay Character & Transforming His Body for 'Kingdom'

Nate is looking to end his painful losing streak for Navy Street and to prove to his father Alvey (Frank Grillo) and everyone else that he's still a viable fighter.

As he gears up for the big moment, Nate hears past echoes of self-doubt in his mind. "You're a great athlete, Nate," the voice says. "I don’t know if you're a great fighter. The difference between good and great -- it's a f**king hundred miles. It's a mindset."

Jonas previously opened up to ET about Nate's struggles outside of the ring as grapples with his sexual identity. "He's still trying to figure it out, and it'll be a journey for sure," the 23-year-old singer/actor said of portraying a gay character. "I'm willing to go wherever I need to go with the story and we'll figure it out when we get there, I guess."

Don't miss the results of Nate's fight when Kingdom airs Wednesday, July 6 at 9 p.m. PT on AT&T Audience Network.