Derek Brunson trained with Jon Jones ... and fought Israel Adesanya, so who'd the UFC star tell TMZ Sports would win in a fight???
Jon Bones Jones.
"I kinda know who would win the fight. Jon Jones would be a little bit too much," Brunson says.
"Jon is a high IQ fighter. So, really the chance of Izzy winning that fight is really catching him and hurting him, and Izzy got the finish in this fight, but he's not really a power guy, he's more of a TKO guy."
"He's gonna put some punches together. But Jon's big, strong, and he's gonna figure it out."
Jones and Adesanya have beef ... it all started when Izzy told us he was a G.O.A.T. killer earlier this year. Jon responded ... and the rivalry's only intensified since ... and both guys say they want to fight.
Brunson is down to watch the 2 champs battle ... but he also wants another crack at Adesanya himself.
Izzy stopped Brunson with a flurry of punches and kicks at the end of the 1st round when they fought in November 2018.
Derek's on a 2-fight win streak -- and he's currently ranked 9th in the division -- but he reveals the secret weapon that's gonna land him the big time rematch.