The matchup was part of Dream's Super Hulk Tournament. At a news conference Monday, Canseco had made it known he was intimidated by his opponent.
"I'm not gonna lie to you: I'm scared," Canseco said. "This guy is huge. I'm a 44-year-old rookie and have had a lot of challenges in my baseball career. Hopefully, I can do well."
Canseco, whose ring experience was limited to celebrity boxing bouts, made several efforts at swinging with hooks and middle kicks. However, his 7-foot-2 Korean opponent was impervious and walked down the former Oakland A's slugger with big pawing punches.
According to Canseco, a right knee injury incurred during training caused him to trip after he threw a middle kick.
Choi, who entered the fight with a 1-2 record and the nickname "Techno Goliath," followed Canseco to the mat and unleashed some additional strikes. The merciful end came soon after.