17-fight UFC veteran who fought 3 world champions announces MMA retirement

Longtime UFC bantamweight Brian Kelleher has decided to call it a career.

Kelleher, AKA "Boom" makes his choice after 40 professional fights, 17 of those coming in the UFC Octagon against a murderer's row in the bantamweight division. We're talking fights with former champs and title challengers alike, including Umar Nurmagomedov, Cody Garbrandt, John Lineker, Renan Barao, 'Chito' Vera, and more.

Brian Kelleher has decided to hang up his gloves. | Jasen Vinlove-Imagn Images

"Boom" Says Fighting Has Come To A Close

The 38-year-old Kelleher hangs up the gloves on a four-fight losing streak, his UFC release coming last fall. This put things into perspective for Kelleher, debating in October whether or not he'd continue fighting.

Brian Kelleher on UFC Legacy, Best Moment and Fight That Got Away

On Wednesday, Kelleher announced his retirement on social media.

"I don’t know what’s next but it seems fighting has come to an end. What a journey. Thank you all who have supported me. Love you. BOOM," Kelleher wrote on 'X'.

"I would have loved one more fight with the UFC in front of my home fans, but sometimes this is just the way it goes."

I don’t know what’s next but it seems fighting has come to an end. What a journey. Thank you all who have supported me. Love you. BOOM
— Brian BOOM Kelleher (@brianboom135) February 26, 2025

Brian Kelleher was not drafted in the GFL's inaugural 2025 draft. In the UFC since 2017, he racked up $250,000 worth of performance bonuses, 3 of which came by his signature guillotine choke.

Outside of fighting, New York's Kelleher loves to rap and make music.

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