UK light heavyweight Buatsi earned a win yet unimpressive beginning to his career under recent management with a points victory over Zach Parker in the Manchester arena.
The Olympic bronze medallist's punch output appeared to earn him a judges' verdict in a close 10-round fight at the boxing arena.
But Parker landed significant shots, connecting with powerful individual punches in a fight where the techniques never quite clicked, with excessive holding disrupting the action.
The officials scored it 96-94 for to Buatsi, with the final judge a 95-95 draw.
"It wasn't my greatest showing but what defines champions? They succeed," the victor commented in the ringside as he was greeted with negative reactions from the audience.
The British fighter returned to winning ways after his initial pro loss - an epic battle with Callum Smith in February - to secure a twentieth professional win.
Some ringside observers felt Parker, thirty-one, should have been awarded the win but the contender endured the second defeat of his 28-match professional journey.
Buatsi Secures Win in Slow Affair
His career development has plateaued in recent times through management issues and considerable time of inactivity.
Once tipped as the rising talent of the British fight scene, he now is positioned trying to achieve expectations - maybe in what feels like a final roll of the dice - under recent support.
He opened tentatively, with the two boxers ready to overcommit in a calculated early stages.
Parker, whose single earlier setback came at super middleweight against his former opponent in two years ago after breaking his hand in the contest, was participating in his second bout at light heavyweight.
By the halfway stage, the underdog had kept it close, making life awkward for Buatsi, who utilized a tight guard to barely take the cleaner rounds.
The spectators' acceptance decreased during regular grabbing, with the challenger falling to the floor various instances during grappling.
Parker closed well, but several stanzas were hard to judge. However, previous titleholder the boxing analyst - commentating on Dazn - had it particularly wide for Parker, awarding Buatsi just a single round.
Buatsi progresses, but with the presence of heavy hitter David Benavidez, and Russian star Dmitry Bivol dominating the weight class, the road to world glory - on this evidence - still looks steep.
Ricky Hatton Homage Motivates Manchester Derby Contest
In the co-main event, Lyndon Arthur beat Rea by close verdict in a terrific all-Manchester battle to capture the European light-heavyweight belt.
The venue grew hushed for a profoundly moving memorial before the fight as ten bells rang in honor of Manchester's own Ricky Hatton, who passed away 46 years old in last month.
It was the initial significant broadcast boxing event in the urban center since the passing of Hatton. As the concluding sound ended, the quiet transitioned to a chant of "only one Hatton".
The competition within the ring matched the sentiment. The eventual winner was sent to the canvas by a significant blow flush on the chin in the early round, getting up unsteadily to his position on the referee's count.
But the traditional red shorts of the fighter soon came forward again. On the opposite side, the opponent - in competitive blue - was injured soon, noticeable damage appearing under his face as the pair landed punishing blows.
The challenger, 27, delivered effective strikes but the champion, thirty-four, fought fire with fire with powerful upward punches as the action seldom decreased over twelve rounds.
The victor narrowly won the verdict with judges scorecards of draw, narrow lead and clearer margin, but the two athletes were determined and courageous, everything their hero the legend represented.
