UK light-heavyweight Buatsi secured a victory yet underwhelming debut to life under recent management with a unanimous decision over Zach Parker in the Manchester arena.
The Olympic medal winner's work rate seemingly secured him a majority decision in a tight 10-round contest at the boxing arena.
But the challenger found success, landing some telling clean blows in a fight where the techniques didn't complement each other, with frequent clinching marring the contest.
The scoring judges judged it 96-94 in favor to Buatsi, with the remaining official a 95-95 draw.
"It wasn't my greatest performance but what defines champions? They succeed," Buatsi commented in the arena as he was faced negative reactions from the spectators.
The Londoner got back to winning after his maiden career setback - an thrilling contest with Callum Smith in last winter - to earn a 20th career victory.
Some ringside observers believed Parker, thirty-one, should have been awarded the win but the contender endured the second defeat of his 28-bout professional journey.
The Champion Claims Victory in Slow Affair
His career development has stalled in recent years through contract problems and considerable time of lack of fights.
Earlier forecast as the future of UK boxing, he now finds himself trying to realize his potential - maybe in what feels like a ultimate opportunity - under fresh management.
He started carefully, with neither fighter willing to take risks in a calculated opening few rounds.
Parker, whose only previous defeat came at super middleweight against John Ryder in 2022 after breaking his hand mid-fight, was making just his second fight at light heavyweight.
By the halfway stage, Parker had made it competitive, creating difficulties for Buatsi, who operated with a tight guard to edge the more effective periods.
The spectators' acceptance diminished because of constant clinching, with the challenger falling to the floor various instances during close exchanges.
Parker closed well, but multiple periods were challenging to assess. Although, previous titleholder Carl Frampton - working with Dazn - had it strongly leaning for the challenger, awarding Buatsi just only one stanza.
The victor progresses, but with the likes of hard hitter David Benavidez, and Eastern European fighter Bivol dominating the weight class, the journey to titles - on this evidence - still seems difficult.
Ricky Hatton Memorial Inspires All-Manchester Battle
In the co-main event, Lyndon Arthur overcame Bradley Rea by split-decision in a terrific local rivalry fight to capture the European light-heavyweight belt.
The arena became quiet for a deeply poignant tribute before the fight as a bell ceremony sounded in remembrance of Manchester's own Hatton, who died 46 years old in last month.
It was the first major televised boxing event in the city since the passing of Hatton. As the concluding sound ended, the silence gave way to a roar of "there's only one Ricky Hatton".
The fighting during the bout matched the feeling. Arthur was knocked down by a left hook flush on the chin in the early round, getting up unsteadily to his feet on the eight count.
But the red-colored shorts of Arthur soon came forward again. Across the ring, the opponent - in competitive blue - was damaged early, noticeable damage forming under his eye as the fighters exchanged hard punches.
Rea, 27, connected with strong blows but the champion, 34, fought fire with fire with stinging uppercuts as the intensity rarely dropped over the full distance.
Arthur edged the result with judges scorecards of 114-114, 115-113 and wider gap, but both fighters were determined and brave, everything their inspiration the legend embodied.
