UK light heavyweight Buatsi secured a victory yet unimpressive beginning to his career under fresh promotional backing with a points victory over Zach Parker in the Manchester arena.
The Olympic medal winner's work rate seemingly secured him a majority decision in a competitive 10-round bout at the Manchester venue.
But the challenger found success, connecting with powerful individual punches in a match where the techniques didn't complement each other, with excessive holding spoiling the action.
Two judges judged it 96-94 in favor to Buatsi, with the third a 95-95.
"It wasn't my finest showing but how do champions respond? They succeed," Buatsi stated in the arena as he was greeted with negative reactions from the spectators.
The Londoner returned to winning ways after his first professional defeat - an epic battle with his previous opponent in last winter - to claim a twentieth professional win.
Various analysts felt the challenger, 31, merited the decision but the Derbyshire fighter suffered the second loss of his 28-bout professional journey.
Buatsi Claims Win in Uneventful Encounter
His career development has slowed in recent times through management issues and considerable time of inactivity.
Previously predicted as the future of British boxing, he now stands trying to fulfil that early promise - possibly in what seems like a ultimate opportunity - under new promotional backing.
He opened tentatively, with the two boxers ready to take risks in a cagey early stages.
The challenger, whose single earlier setback came at super-middleweight against John Ryder in two years ago after damaging his hand during the bout, was making just his second fight at the higher weight class.
By the halfway stage, the underdog had made it competitive, creating difficulties for Buatsi, who utilized a solid defense to edge the cleaner rounds.
The audience's tolerance wore thin because of constant clinching, with the challenger slipping to the canvas multiple occasions during clinches.
The underdog finished the stronger, but many rounds were hard to judge. Nevertheless, ex-champion the boxing analyst - commentating on Dazn - had it significantly in favor for the challenger, giving Buatsi just one round.
The victor advances, but with the caliber of heavy hitter David Benavidez, and Eastern European fighter Dmitry Bivol dominating the weight class, the road to world glory - judging by this showing - still seems difficult.
Ricky Hatton Homage Fuels Local Rivalry Contest
In the secondary fight, Lyndon Arthur overcame Bradley Rea by split-decision in a outstanding Manchester vs Manchester contest to secure the European light heavyweight belt.
The venue became quiet for a deeply poignant memorial ahead of the contest as 10 bells tolled in honor of local hero Hatton, who succumbed aged 46 in recently.
It was the premier televised boxing event in the city since the passing of Hatton. As the last bell disappeared, the quiet transitioned to a chant of "there's just one Ricky Hatton".
The competition during the bout equaled the emotion. Arthur was floored by a significant blow flush on the chin in the early round, getting up unsteadily to his feet on the referee's count.
But the red-colored equipment of Arthur soon came forward again. On the opposite side, the opponent - in rival City blue - was damaged soon, heavy swelling developing under his face as the duo traded powerful shots.
The challenger, twenty-seven, connected with strong blows but the champion, 34, fought fire with fire with stinging uppercuts as the intensity hardly diminished over the full distance.
Arthur barely secured the decision with judges scorecards of 114-114, 115-113 and 115-112, but each competitor were determined and brave, all the qualities their inspiration the legend represented.
