Jon Jones Teases Fight Return Despite Looming Suspension

He's staring down the barrel of a 4-year suspension, but Jon Jones says he's NOT giving up his fight career -- and he's still training as if he'll be back in the near future.

TMZ Sports broke the story ... Jones was popped for steroids in August after UFC 214 -- the second time he's tested positive for a banned substance in the last 2 years.

Jones has been provisionally suspended and is now facing 4 years in the penalty box once the United States Anti-Doping Agency (USADA) metes out the official punishment.

But Jon isn't waving the white flag just yet ... in fact, he busted out the UFC gear and hit the mitts with a trainer -- insisting, "If I made it to the top of the mountain once, I can do it again."

The question ... is he looking to switch sports?

He added another caption saying, "I believe there are talents inside of me I haven't even discovered yet. There's nothing I put my mind to that I can't achieve, just got to be willing to put in the work."

Jones is a freak athlete. He's only 30. Guessing he's not planning on doing NOTHING.