UK light heavyweight Buatsi earned a win yet unimpressive debut to life under recent management with a decision win over Zach Parker in Manchester.
The Olympic medal winner's work rate appeared to earn him a judges' verdict in a close 10-round fight at the Co-op Live Arena.
But the challenger found success, connecting with powerful clean blows in a fight where the styles didn't complement each other, with frequent clinching disrupting the fight.
The officials judged it 96-94 for to the winner, with the final judge a 95-95 draw.
"It wasn't my best showing but what defines champions? They succeed," Buatsi stated in the arena as he was met by boos from the spectators.
The British fighter bounced back after his first professional defeat - an epic battle with Callum Smith in February - to secure a twentieth professional win.
Some ringside observers believed Parker, 31, merited the victory but the Derbyshire fighter endured the second loss of his 28-fight professional journey.
Buatsi Earns Win in Dull Match
His career development has plateaued in recent years through management issues and considerable time of lack of fights.
Once tipped as the next star of UK boxing, he now finds himself trying to achieve expectations - perhaps in what seems like a ultimate opportunity - under recent support.
He began cautiously, with both competitors willing to take risks in a cagey early stages.
The challenger, whose sole prior loss came at super-middleweight against John Ryder in 2022 after suffering a hand injury in the contest, was competing in only his second bout at light heavyweight.
By the fight's midpoint, the underdog had made it competitive, making life awkward for the favorite, who operated with a tight guard to edge the more effective periods.
The audience's tolerance wore thin during constant clinching, with the challenger slipping to the canvas various instances during clinches.
Parker finished the stronger, but many rounds were hard to judge. Nevertheless, former world champion Carl Frampton - providing analysis for the broadcast network - had it significantly in favor for Parker, scoring for Buatsi just one round.
Buatsi moves on, but with the caliber of power puncher David Benavidez, and Russian star Dmitry Bivol ruling the division, the road to world glory - judging by this showing - still seems difficult.
Hatton Homage Fuels Manchester Derby Contest
In the secondary fight, Arthur defeated Bradley Rea by divided decision in a excellent all-Manchester contest to secure the continental belt.
The venue became quiet for a extremely emotional memorial prior to the bout as a bell ceremony sounded in honor of local hero Ricky Hatton, who died aged 46 in September.
It was the initial significant broadcast match card in the location since Hatton's passing. As the last bell faded, the quiet transitioned to a roar of "there's only one Ricky Hatton".
The fighting within the ring matched the emotion. Arthur was floored by a left hook squarely on the face in the initial stage, rising shakily to his position on the eight count.
But the Manchester United-red shorts of Arthur soon came forward again. Across the ring, the opponent - in competitive blue - was marked up quickly, significant bruising appearing under his face as the pair traded powerful shots.
Rea, twenty-seven, landed power punches but Arthur, 34, matched the intensity with powerful upward punches as the intensity hardly diminished over 12 rounds.
Arthur narrowly won the result with scoring tallies of even score, close margin and wider gap, but both fighters were relentless and brave, exactly what their inspiration the legend embodied.
