MMA Hero Phoenix Jones -- I Chased Down Stabbing Suspect ... Disarmed Alleged Bad Guy

Real-life superhero Phoenix Jones claims he's saved the day again ... this time, the MMA fighter says he chased down a stabbing suspect in Connecticut and DISARMED the perp.

TMZ Sports has learned ... Jones -- a World Series of Fighting mixed martial artist -- real name Ben Fodor -- filled out a statement with the New Haven PD saying he was walking down the street Friday when, "I saw a man being chased who was bleeding from his face."

Fodor -- who made headlines as a real-life crime-fighter in Seattle -- says he put on his bulletproof vest and confronted a man he believed to be the "stabbing suspect."

Jones says the man then displayed a hunting knife ... so he proceeded to disarm the alleged bad guy. Once he believed the threat was neutralized, Jones says he went back and waited with the victim until medics arrived.

The 26-year-old undefeated MMA fighter says he captured the entire incident on his go-pro camera ... and handed the footage over to police.

Cops confirm a report was made -- but say they are still investigating the matter ... including Phoenix's role in the incident.