How bad do skateboarding injuries hurt? Bad enough to willingly go a round with an MMA superstar in the Octagon ... 'cause Ryan Sheckler says he'd rather take a punch from Conor McGregor than relive his worst encounter with concrete.
Sheckler -- who has had his fair share of skating injuries -- says the temporary pain from getting KO'd wouldn't even come close to what he's gone through.
"You gotta feel like I'd be knocked down in 10 seconds," Sheckler says. "The skateboarding injuries suck. The concrete sucks. So if I can get hit real quick and out, I'll take that."
"It just seems a lot simpler ... and no recovery time at the end."
Check out the clip ... Shecks also weighs in on who he'd take in McGregor vs. Diaz 3 ... if it ever happens.