British light-heavyweight Buatsi secured a victory yet disappointing debut to his career under new promoters with a points victory over Zach Parker in the Manchester arena.
The Olympic bronze medallist's punch output seemingly secured him a majority decision in a competitive 10-round fight at the Manchester venue.
But Parker landed significant shots, landing some telling individual punches in a fight where the styles didn't complement each other, with constant grabbing marring the contest.
The scoring judges scored it 96-94 to the winner, with the remaining official a 95-95.
"It wasn't my greatest performance but what defines champions? They prevail," Buatsi stated in the arena as he was faced negative reactions from the spectators.
The British fighter got back to winning after his initial pro loss - an epic battle with Callum Smith in last winter - to claim a twentieth professional win.
Some ringside observers felt the challenger, thirty-one, merited the win but the British boxer experienced the second defeat of his 28-fight professional journey.
Buatsi Secures Win in Uneventful Match
Buatsi's progress has stalled in recent times through promotional disputes and long spells of inactivity.
Once tipped as the rising talent of the British fight scene, he now stands trying to achieve expectations - perhaps in what feels like a last chance - under recent support.
He began cautiously, with the two boxers prepared to take risks in a cagey initial rounds.
Parker, whose single earlier setback came at the lower weight class against his former opponent in 2022 after suffering a hand injury during the bout, was making just his second bout at light heavyweight.
By the fight's midpoint, Parker had made it competitive, creating difficulties for the favorite, who utilized a solid defense to narrowly win the more effective stanzas.
The spectators' acceptance diminished because of regular grabbing, with the challenger slipping to the canvas various instances during clinches.
The underdog ended stronger, but many rounds were challenging to assess. However, previous titleholder the boxing analyst - working with the broadcast network - had it particularly wide for Parker, awarding Buatsi just one round.
The victor progresses, but with the caliber of hard hitter David Benavidez, and Eastern European fighter Dmitry Bivol leading the category, the road to world glory - on this evidence - still looks steep.
Ricky Hatton Memorial Inspires Manchester Derby Battle
In the secondary fight, Arthur defeated Rea by split-decision in a terrific all-Manchester battle to win the European light-heavyweight title.
The arena fell silent for a profoundly moving memorial ahead of the contest as ten bells tolled in honor of Manchester's own Hatton, who passed away at age 46 in September.
It was the first major televised fight night in the urban center since Hatton's death. As the last bell ended, the silence transitioned to a shout of "there's just one Ricky Hatton".
The competition within the ring equaled the feeling. Arthur was knocked down by a left hook squarely on the face in the early round, rising shakily to his footing on the referee's count.
But the red-colored shorts of the fighter soon pressed ahead again. On the opposite side, the opponent - in opposing blue - was damaged quickly, significant bruising forming under his face as the pair landed punishing blows.
The challenger, twenty-seven, delivered effective strikes but the champion, thirty-four, responded in kind with powerful upward punches as the intensity rarely dropped over the full distance.
The victor narrowly won the verdict with scoring tallies of even score, 115-113 and clearer margin, but each competitor were determined and full of heart, all the qualities their hero Hatton represented.
