Feeling good TMZSports.com
Frank Martin's hoping more people keep doubting him ahead of his fight against Gervonta "Tank" Davis ... telling TMZ Sports he uses the criticism as "fuel" -- and can't wait to shock the world!!
The WBA Lightweight World Title fight is slated for June 15 at the MGM Grand in Las Vegas ... and Martin (18-0 w/ 12 KOs) says he feels confident to get in the ring with one of the best pound-for-pound boxers in the world.
"I got a lot of things that him, the world, a lot of people may not expect that I got," Martin told us this week.