By TMZ Sports

Mickey Rourke is getting major support from boxing legend Bernard Hopkins -- who tells TMZ Sports he's PROUD of the 62-year-old for getting back in the ring ... and thinks he has a real shot to win!

49-year-old Hopkins -- who says he's still open to fighting into his 50s -- says he commends Rourke for taking a fight with a 29-year-old fighter in Russia on November 28th.

"The only way you're gonna know what you're capable of is by challenging yourself," Hopkins says.

"Most people can't see themselves doing what I or Mickey have done. So they talk down to it. That's a motivation for me. And I'm sure it is for him."

So the question ... can Rourke actually win the fight?

"I'm gonna go with the experienced guy [Rourke] who knows how to take care of himself," Hopkins says ... "It's not a slam dunk that he'll win, but at the least I think it's going to be a competitive fight."

As for Bernard's future in the ring -- he tells us, "I'm going to make a decision if I'll fight again after the holidays. But I do have an option with HBO."

He adds, "If I fight, it's not going to be a fight just to fight, it's going to be a fight that I could just as well lose if I'm not on my game. I want to push the envelope like I always have."