UK light heavyweight Buatsi secured a victory yet unimpressive beginning to his career under recent management with a decision win over Zach Parker in the Manchester arena.
The Olympic medal winner's activity level appeared to earn him a split decision in a tight 10-round fight at the Manchester venue.
But Parker found success, connecting with powerful single shots in a fight where the styles didn't complement each other, with constant grabbing spoiling the contest.
The scoring judges judged it 96-94 to Buatsi, with the remaining official a 95-95 draw.
"It wasn't my best display but what do champions do? They succeed," Buatsi said in the arena as he was greeted with disapproval from the crowd.
The British fighter bounced back after his initial pro loss - an epic battle with Callum Smith in February - to claim a 20th pro success.
Various analysts felt Parker, 31, should have been awarded the win but the contender suffered the second setback of his 28-bout career.
Buatsi Earns Victory in Uneventful Affair
The fighter's advancement has slowed in the past few years through contract problems and extended periods of inactivity.
Once tipped as the next star of UK boxing, he now is positioned trying to realize his potential - possibly in what seems like a final roll of the dice - under recent support.
He opened tentatively, with the two boxers willing to overcommit in a calculated early stages.
The challenger, whose single earlier setback came at the lower weight class against John Ryder in two years ago after suffering a hand injury during the bout, was participating in his second appearance at light-heavyweight.
By the halfway stage, Parker had kept it close, making life awkward for the favorite, who worked behind a protective stance to barely take the better periods.
The audience's tolerance diminished because of constant clinching, with the challenger slipping to the canvas multiple occasions during close exchanges.
Parker finished the stronger, but several stanzas were challenging to assess. Nevertheless, former world champion Carl Frampton - working with the broadcast network - had it significantly in favor for the challenger, awarding Buatsi just one round.
The victor advances, but with the caliber of heavy hitter David Benavidez, and Russian champion Dmitry Bivol ruling the division, the path to championship success - on this evidence - still appears challenging.
Ricky Hatton Homage Motivates Manchester Derby Contest
In the co-main event, Arthur beat Rea by split-decision in a excellent all-Manchester contest to secure the European light-heavyweight title.
The stadium became quiet for a deeply poignant homage before the fight as ten bells tolled in honor of the city's native Hatton, who passed away 46 years old in last month.
It was the first major televised fight night in the urban center since the passing of Hatton. As the last bell disappeared, the silence gave way to a shout of "there's only one Hatton".
The competition inside the ropes reflected the emotion. The eventual winner was knocked down by a significant blow directly to the jaw in the initial stage, getting up unsteadily to his feet on the referee's count.
But the red-colored shorts of Arthur soon came forward again. From the other corner, the opponent - in rival City blue - was damaged quickly, significant bruising appearing under his orbital area as the duo landed powerful shots.
Rea, 27, delivered effective strikes but Arthur, thirty-four, matched the intensity with powerful upward punches as the pace seldom decreased over the full distance.
Arthur edged the verdict with official scores of draw, close margin and clearer margin, but both fighters were relentless and courageous, all the qualities their hero Hatton stood for.
