British light heavyweight Buatsi made a winning yet underwhelming debut to life under recent management with a decision win over Zach Parker in Manchester.
The Olympic bronze medallist's activity level seemingly secured him a majority decision in a competitive 10-round bout at the Co-op Live Arena.
But the challenger had his moments, landing some telling single shots in a fight where the styles never quite clicked, with constant grabbing disrupting the contest.
The scoring judges had it 96-94 in favor to Buatsi, with the third a even score.
"It wasn't my finest showing but what defines champions? They succeed," the victor commented in the ringside as he was faced boos from the crowd.
The British fighter returned to winning ways after his maiden career setback - an epic battle with his previous opponent in last winter - to earn a twentieth professional win.
Various analysts believed Parker, 31, deserved the win but the Derbyshire fighter suffered the second defeat of his 28-bout career.
The Champion Claims Victory in Uneventful Encounter
Buatsi's progress has stalled in the past few years through management issues and long spells of inactivity.
Previously predicted as the next star of British boxing, he now stands trying to realize his potential - maybe in what feels like a ultimate opportunity - under recent support.
He opened tentatively, with the two boxers prepared to take risks in a cagey opening few rounds.
Parker, whose single earlier setback came at super middleweight against John Ryder in 2022 after suffering a hand injury in the contest, was competing in only his second bout at the higher weight class.
By the fight's midpoint, the underdog had made it competitive, making life awkward for the favorite, who utilized a protective stance to edge the better periods.
The crowd's patience diminished because of frequent holding, with Parker falling to the floor several times during close exchanges.
Parker finished the stronger, but multiple periods were difficult to score. Although, previous titleholder the boxing analyst - working with Dazn - had it strongly leaning for Parker, scoring for Buatsi just a single round.
Buatsi advances, but with the likes of hard hitter David Benavidez, and Russian champion Bivol ruling the division, the journey to titles - on this evidence - still looks steep.
Hatton Memorial Motivates All-Manchester Fight
In the supporting bout, Lyndon Arthur overcame Rea by split-decision in a outstanding all-Manchester battle to secure the European light heavyweight championship.
The arena became quiet for a profoundly moving homage prior to the bout as 10 bells sounded in remembrance of local hero Ricky Hatton, who died aged 46 in last month.
It was the initial significant broadcast boxing event in the city since the passing of Hatton. As the final chime ended, the quiet became a roar of "there's only one Ricky Hatton".
The competition inside the ropes matched the emotion. The eventual winner was floored by a significant blow squarely on the jaw in the initial stage, standing uncertainly to his footing on the eight count.
But the red-colored shorts of Arthur soon advanced again. On the opposite side, the opponent - in rival City blue - was marked up early, noticeable damage developing under his orbital area as the pair traded hard punches.
Rea, 27, delivered effective strikes but Arthur, 34, matched the intensity with powerful upward punches as the pace hardly diminished over twelve rounds.
The victor barely secured the decision with scoring tallies of 114-114, narrow lead and clearer margin, but the two athletes were persistent and courageous, exactly what their idol the legend embodied.
