UK light-heavyweight Buatsi made a winning yet unimpressive beginning to life under recent management with a decision win over Zach Parker in the Manchester arena.
The Olympic bronze medallist's work rate appeared to earn him a majority decision in a close 10-round bout at the Manchester venue.
But the challenger found success, landing some telling individual punches in a fight where the approaches failed to mesh, with constant grabbing disrupting the contest.
The officials judged it 96-94 in favor to the winner, with the remaining official a even score.
"It wasn't my greatest display but how do champions respond? They succeed," the victor said in the arena as he was faced negative reactions from the spectators.
The Londoner bounced back after his first professional defeat - an memorable fight with his previous opponent in last winter - to secure a 20th career victory.
Several boxing experts thought the challenger, thirty-one, should have been awarded the win but the Derbyshire fighter suffered the second setback of his 28-fight career.
The Champion Secures Triumph in Slow Encounter
Buatsi's progress has plateaued in recent years through contract problems and long spells of inactivity.
Previously predicted as the next star of British boxing, he now stands trying to realize his potential - perhaps in what appears to be a ultimate opportunity - under fresh management.
He opened tentatively, with the two boxers prepared to take risks in a tentative initial rounds.
Parker, whose only previous defeat came at super-middleweight against his former opponent in two years ago after damaging his hand mid-fight, was competing in only his second appearance at light heavyweight.
By the halfway stage, the underdog had kept it close, making life awkward for the favorite, who operated with a solid defense to edge the better periods.
The audience's tolerance diminished during constant clinching, with Parker falling to the floor several times during grappling.
The underdog finished the stronger, but many rounds were difficult to score. Although, previous titleholder the boxing analyst - working with Dazn - had it significantly in favor for the challenger, awarding Buatsi just only one stanza.
The victor moves on, but with the presence of power puncher David Benavidez, and Eastern European fighter Bivol leading the category, the path to championship success - based on this performance - still looks steep.
Ricky Hatton Tribute Fuels Local Rivalry Fight
In the secondary fight, Arthur defeated Rea by divided decision in a excellent local rivalry fight to capture the continental championship.
The stadium fell silent for a deeply poignant memorial prior to the bout as a bell ceremony tolled in honor of the city's native Ricky Hatton, who died at age 46 in last month.
It was the first major televised fight night in the city since Hatton's passing. As the last bell disappeared, the stillness transitioned to a chant of "there's just one Ricky Hatton".
The action within the ring matched the emotion. The eventual winner was knocked down by a powerful punch flush on the chin in the second round, getting up unsteadily to his position on the referee's count.
But the traditional red equipment of Arthur soon came forward again. On the opposite side, Rea - in rival City blue - was damaged early, noticeable damage forming under his orbital area as the fighters traded hard punches.
Rea, 27, landed power punches but the champion, thirty-four, fought fire with fire with effective uppercuts as the pace rarely dropped over twelve rounds.
Arthur narrowly won the decision with judges scorecards of 114-114, close margin and wider gap, but each competitor were persistent and brave, all the qualities their inspiration Hatton embodied.
