British light-heavyweight Buatsi secured a victory yet unimpressive beginning 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 appeared to earn him a majority decision in a competitive 10-round fight at the Co-op Live Arena.
But the challenger found success, connecting with powerful individual punches in a fight where the styles never quite clicked, with excessive holding spoiling the action.
Two judges had it 96-94 in favor to the winner, with the final judge a 95-95.
"It wasn't my greatest performance but what defines champions? They win," Buatsi stated in the ring as he was faced boos from the crowd.
The British fighter got back to winning after his maiden career setback - an memorable fight with his previous opponent in February - to earn a 20th career victory.
Some ringside observers believed Parker, 31, should have been awarded the win but the contender endured the second setback of his 28-bout professional journey.
Buatsi Claims Triumph in Uneventful Match
His career development has slowed in recent years through management issues and considerable time of inactivity.
Previously predicted as the next star of UK boxing, he now is positioned trying to achieve expectations - possibly in what feels like a last chance - under new promotional backing.
He opened tentatively, with both competitors willing to take risks in a calculated initial rounds.
Parker, whose sole prior loss came at super-middleweight against John Ryder in 2022 after damaging his hand in the contest, was making just his second appearance at light heavyweight.
By the fight's midpoint, the underdog had kept it close, causing problems for the favorite, who utilized a protective stance to edge the better periods.
The spectators' acceptance wore thin because of regular grabbing, with Parker going down multiple occasions during grappling.
Parker closed well, but many rounds were difficult to score. Nevertheless, ex-champion Carl Frampton - working with Dazn - had it significantly in favor for the challenger, giving Buatsi just one round.
Buatsi progresses, but with the presence of hard hitter Benavidez, and Russian star Dmitry Bivol leading the category, the path to championship success - on this evidence - still appears challenging.
Ricky Hatton Memorial Motivates All-Manchester Battle
In the secondary fight, Lyndon Arthur defeated Bradley Rea by close verdict in a terrific local rivalry contest to win the European light heavyweight championship.
The arena fell silent for a deeply poignant memorial ahead of the contest as a bell ceremony tolled in memory of local hero Ricky Hatton, who passed away 46 years old in recently.
It was the first major televised match card in the location since the passing of Hatton. As the last bell disappeared, the quiet gave way to a roar of "only one Ricky Hatton".
The fighting during the bout reflected the emotion. The eventual winner was sent to the canvas by a left hook squarely on the jaw in the second round, getting up unsteadily to his feet on the referee's count.
But the traditional red shorts of the fighter soon advanced again. From the other corner, Rea - in rival City blue - was marked up soon, significant bruising forming under his orbital area as the pair exchanged hard punches.
The challenger, twenty-seven, delivered effective strikes but Arthur, thirty-four, matched the intensity with stinging uppercuts as the pace rarely dropped over the full distance.
Arthur barely secured the result with judges scorecards of draw, close margin and wider gap, but both fighters were persistent and brave, all the qualities their inspiration the legend stood for.
