British light-heavyweight Buatsi secured a victory yet unimpressive debut to his career under fresh promotional backing with a decision win over Zach Parker in the Manchester arena.
The Olympic bronze medallist's punch output seemingly secured him a judges' verdict in a competitive 10-round fight at the boxing arena.
But the challenger found success, connecting with powerful individual punches in a contest where the techniques failed to mesh, with constant grabbing disrupting the action.
The officials scored it 96-94 to Buatsi, with the final judge a even score.
"It wasn't my best showing but what do champions do? They win," Buatsi commented in the ringside as he was faced disapproval from the crowd.
The Londoner bounced back after his first professional defeat - an memorable fight with Callum Smith in last winter - to secure a 20th pro success.
Several boxing experts believed the challenger, thirty-one, merited the victory but the British boxer endured the second loss of his 28-match professional journey.
Buatsi Secures Triumph in Slow Match
His career development has plateaued in recent times through promotional disputes and long spells of inactivity.
Once tipped as the next star of the British fight scene, he now is positioned trying to achieve expectations - perhaps in what appears to be a last chance - under recent support.
He started carefully, with both competitors willing to be aggressive in a tentative early stages.
The challenger, whose sole prior loss came at the lower weight class against his former opponent in 2022 after damaging his hand in the contest, was making just his second fight at the higher weight class.
By the halfway stage, Parker had made it competitive, causing problems for Buatsi, who operated with a tight guard to barely take the more effective periods.
The spectators' acceptance wore thin during constant clinching, with the challenger going down various instances during close exchanges.
The underdog closed well, but many rounds were hard to judge. Although, ex-champion the boxing analyst - commentating on Dazn - had it strongly leaning for the challenger, giving Buatsi just one round.
The victor progresses, but with the likes of hard hitter Benavidez, and Russian star Dmitry Bivol leading the category, the road to world glory - based on this performance - still appears challenging.
Hatton Memorial Motivates All-Manchester Fight
In the co-main event, Arthur defeated Rea by split-decision in a terrific local rivalry fight to secure the European light-heavyweight belt.
The venue grew hushed for a extremely emotional tribute prior to the bout as a bell ceremony rang in memory of Manchester's own Hatton, who succumbed aged 46 in recently.
It was the first major televised boxing event in the urban center since Hatton's passing. As the concluding sound ended, the silence transitioned to a shout of "there's only one Ricky Hatton".
The competition inside the ropes equaled the sentiment. The eventual winner was sent to the canvas by a significant blow flush on the chin in the early round, getting up unsteadily to his footing on the eight count.
But the traditional red shorts of Arthur soon pressed ahead again. On the opposite side, the opponent - in rival City blue - was injured quickly, significant bruising developing under his eye as the fighters landed hard punches.
Rea, 27, connected with strong blows but Arthur, thirty-four, matched the intensity with stinging uppercuts as the pace seldom decreased over the full distance.
Arthur barely secured the verdict with official scores of even score, 115-113 and wider gap, but each competitor were determined and courageous, all the qualities their inspiration Hatton represented.
