British light heavyweight Buatsi made a winning yet underwhelming debut to his career under new promoters with a unanimous decision over Zach Parker in Manchester.
The Olympic bronze medallist's activity level seemingly secured him a judges' verdict in a competitive ten-round contest at the boxing arena.
But the challenger found success, delivering effective individual punches in a match where the techniques failed to mesh, with constant grabbing spoiling the fight.
The officials scored it 96-94 for to Buatsi, with the third a even score.
"It wasn't my best display but how do champions respond? They prevail," the victor commented in the ringside as he was met by disapproval from the crowd.
The Londoner got back to winning after his maiden career setback - an memorable fight with his previous opponent in February - to earn a twentieth professional win.
Various analysts thought Parker, thirty-one, deserved the decision but the British boxer experienced the second setback of his 28-match career.
The Champion Earns Win in Dull Encounter
Buatsi's progress has plateaued in recent years through management issues and extended periods of inactivity.
Earlier forecast as the future of the British fight scene, he now finds himself trying to achieve expectations - perhaps in what seems like a last chance - under recent support.
He opened tentatively, with neither fighter willing to be aggressive in a cagey initial rounds.
The challenger, whose sole prior loss came at super-middleweight against his former opponent in 2022 after breaking his hand mid-fight, was making just his second appearance at light-heavyweight.
By the middle rounds, the underdog had stayed in contention, causing problems for Buatsi, who operated with a protective stance to narrowly win the cleaner rounds.
The crowd's patience decreased because of regular grabbing, with Parker falling to the floor multiple occasions during clinches.
The underdog closed well, but multiple periods were challenging to assess. Although, previous titleholder the boxing analyst - providing analysis for the broadcast network - had it strongly leaning for the challenger, scoring for Buatsi just only one stanza.
Buatsi progresses, but with the likes of hard hitter David Benavidez, and Russian champion Bivol leading the category, the journey to titles - based on this performance - still appears challenging.
Ricky Hatton Memorial Fuels Manchester Derby Battle
In the co-main event, Lyndon Arthur overcame Rea by divided decision in a excellent all-Manchester fight to secure the continental title.
The arena became quiet for a deeply poignant memorial prior to the bout as a bell ceremony tolled in honor of local hero Hatton, who died 46 years old in recently.
It was the premier televised fight night in the urban center since Hatton's death. As the final chime faded, the quiet gave way to a shout of "there's only one Hatton".
The competition inside the ropes matched the sentiment. The eventual winner was sent to the canvas by a powerful punch squarely on the jaw in the initial stage, standing uncertainly to his position on the referee's count.
But the red-colored attire of Arthur soon advanced again. From the other corner, Rea - in competitive blue - was damaged soon, significant bruising developing under his face as the duo traded hard punches.
The challenger, 27, delivered effective strikes but the champion, 34, responded in kind with stinging uppercuts as the pace hardly diminished over the full distance.
The victor barely secured the verdict with judges scorecards of even score, close margin and clearer margin, but the two athletes were determined and brave, everything their inspiration Hatton stood for.
