Brantley Gilbert may look like a tough guy on the outside, with his all-black attire and leather accessories, but there is one thing he's afraid of and he even has nightmares about it. His biggest fear involves country star Tim McGraw

Gilbert, who is currently opening for McGraw on his Two Lanes of Freedom Tour, along with Love and Theft, tells Country Weekly that he has recurring nightmares about the 'Highway Don't Care' hitmaker. “I’m telling ya, I keep on having the same nightmare where Tim knocks on the door of my tour bus to go work out with him,” laughs Gilbert.

While that may be a dream come true for fans who are on the same workout level as McGraw --and there probably aren't many-- Gilbert know his body's limits.

He adds, “I mean, I like to do some power lifting and strength training because I just can’t run because of some knee and back problems . . . but Tim? I mean, he is on a whole other level. That man is like the Terminator. I’m pretty sure he bleeds chrome.”

Although he knows he can't necessarily keep up with McGraw in the gym, Gilbert says humorously, "I bought me some Air Jordans and some tall white socks with three stripes at the top and a pair of shorts. I thought I wore a large in shorts, but I didn’t know there was a new style in shorts. These shorts hang down past my calf muscles. I also got a shirt that says ‘Run Like a Boss’ since my nickname is Boss.”

Donning his brand spankin' new workout apparel, the 'Halfway to Heaven' singer took a selfie and texted it to Tim. “I was all duded up and my socks were all pulled up,“ he says laughing, “with the message: ‘Anyone wanna play ball?‘”

At least his nightmares don't terrify him too much. Judging from Gilbert's super-fit physique, he could definitely keep up with the country music icon for at least a little while. Plus, his gorgeous fiance Jana Kramer thinks he's super cute, and he didn't have to perform any superhuman feats of strength to get her!