UK light-heavyweight Buatsi secured a victory yet underwhelming start to life under recent management with a decision win over Zach Parker in Manchester.
The Olympic bronze medallist's punch output appeared to earn him a judges' verdict in a competitive ten-round contest at the Manchester venue.
But the challenger found success, delivering effective individual punches in a fight where the styles never quite clicked, with constant grabbing marring the contest.
The officials judged it 96-94 for to Buatsi, with the remaining official a even score.
"It wasn't my greatest showing but how do champions respond? They win," the victor commented in the arena as he was greeted with negative reactions from the crowd.
The British fighter got back to winning after his first professional defeat - an memorable fight with Callum Smith in last winter - to secure a twentieth professional win.
Some ringside observers believed Parker, 31, merited the win but the contender endured the second setback of his 28-match professional journey.
The Champion Claims Win in Slow Encounter
His career development has stalled in recent years through management issues and extended periods of inactivity.
Earlier forecast as the future of British boxing, he now stands trying to realize his potential - maybe in what seems like a last chance - under new promotional backing.
He opened tentatively, with both competitors willing to take risks in a cagey opening few rounds.
The challenger, whose sole prior loss came at the lower weight class against his former opponent in 2022 after breaking his hand in the contest, was participating in his second fight at light-heavyweight.
By the fight's midpoint, the underdog had kept it close, creating difficulties for Buatsi, who worked behind a tight guard to barely take the better stanzas.
The crowd's patience decreased during regular grabbing, with the challenger slipping to the canvas several times during close exchanges.
The underdog closed well, but multiple periods were difficult to score. Nevertheless, former world champion the boxing analyst - commentating on Dazn - had it significantly in favor for Parker, scoring for Buatsi just a single round.
Buatsi advances, but with the likes of hard hitter Benavidez, and Russian champion Bivol leading the category, the journey to titles - based on this performance - still appears challenging.
Ricky Hatton Memorial Inspires All-Manchester Fight
In the supporting bout, Lyndon Arthur defeated Rea by split-decision in a outstanding local rivalry fight to capture the continental championship.
The arena grew hushed for a deeply poignant tribute prior to the bout as a bell ceremony sounded in memory of the city's native Hatton, who died 46 years old in last month.
It was the first major televised fight night in the city since the passing of Hatton. As the last bell disappeared, the quiet became a chant of "there's just one Ricky Hatton".
The competition during the bout reflected the feeling. Arthur was knocked down by a left hook squarely on the jaw in the second round, standing uncertainly to his feet on the eight count.
But the Manchester United-red attire of the fighter soon pressed ahead again. Across the ring, the opponent - in competitive blue - was damaged quickly, noticeable damage forming under his orbital area as the duo traded powerful shots.
The challenger, twenty-seven, connected with strong blows but Arthur, 34, fought fire with fire with stinging uppercuts as the intensity hardly diminished over twelve rounds.
The victor edged the verdict with judges scorecards of draw, 115-113 and clearer margin, but the two athletes were determined and courageous, all the qualities their hero Hatton embodied.
