British light-heavyweight Buatsi secured a victory yet disappointing beginning to life under fresh promotional backing with a points victory over Zach Parker in Manchester.
The Olympic bronze medallist's activity level likely gained him a split decision in a close ten-round contest at the Co-op Live Arena.
But the challenger landed significant shots, landing some telling single shots in a contest where the styles never quite clicked, with constant grabbing disrupting the fight.
The officials scored it 96-94 in favor to the winner, with the final judge a 95-95.
"It wasn't my greatest display but what defines champions? They succeed," the victor commented in the ringside as he was faced negative reactions from the audience.
The Londoner returned to winning ways after his first professional defeat - an thrilling contest with Callum Smith in last winter - to claim a twentieth professional win.
Some ringside observers believed Parker, thirty-one, deserved the win but the Derbyshire fighter experienced the second setback of his 28-bout career.
Buatsi Secures Victory in Slow Match
The fighter's advancement has slowed in the past few years through management issues and extended periods of inactivity.
Once tipped as the next star of British boxing, he now finds himself trying to realize his potential - possibly in what appears to be a final roll of the dice - under fresh management.
He opened tentatively, with both competitors ready to take risks in a cagey opening few rounds.
The challenger, whose sole prior loss came at super middleweight against his former opponent in two years ago after damaging his hand mid-fight, was making just his second bout at the higher weight class.
By the middle rounds, the underdog had stayed in contention, making life awkward for Buatsi, who operated with a solid defense to barely take the cleaner periods.
The crowd's patience diminished during regular grabbing, with Parker falling to the floor various instances during close exchanges.
Parker ended stronger, but many rounds were hard to judge. Although, former world champion Carl Frampton - commentating on the broadcast network - had it significantly in favor for Parker, awarding Buatsi just a single round.
Buatsi progresses, but with the caliber of heavy hitter Benavidez, and Eastern European fighter Bivol dominating the weight class, the road to world glory - judging by this showing - still seems difficult.
Hatton Homage Inspires All-Manchester Battle
In the secondary fight, Arthur overcame Rea by divided decision in a outstanding Manchester vs Manchester battle to win the continental belt.
The stadium fell silent for a extremely emotional homage prior to the bout as ten bells rang in remembrance of Manchester's own Hatton, who died 46 years old in September.
It was the first major televised boxing event in the urban center since Hatton's death. As the final chime faded, the quiet became a roar of "only one Hatton".
The action within the ring reflected the feeling. Arthur was floored by a powerful punch directly to the face in the initial stage, standing uncertainly to his footing on the eight count.
But the Manchester United-red attire of Arthur soon pressed ahead again. On the opposite side, the opponent - in opposing blue - was damaged quickly, heavy swelling forming under his face as the fighters landed punishing blows.
Rea, 27, landed power punches but Arthur, thirty-four, fought fire with fire with powerful upward punches as the pace seldom decreased over 12 rounds.
The victor narrowly won the decision with judges scorecards of even score, close margin and clearer margin, but both fighters were relentless and full of heart, all the qualities their inspiration the legend embodied.
