British light heavyweight Buatsi made a winning yet disappointing beginning to life under recent management with a decision win 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 fight at the Co-op Live Arena.
But the challenger had his moments, delivering effective single shots in a match where the approaches didn't complement each other, with excessive holding spoiling the contest.
The officials scored it 96-94 to the winner, with the final judge a even score.
"It wasn't my best display but what defines champions? They win," the victor commented in the ring as he was greeted with negative reactions from the crowd.
The British fighter bounced back after his first professional defeat - an thrilling contest with his previous opponent in February - to secure a 20th pro success.
Various analysts thought the challenger, 31, should have been awarded the decision but the Derbyshire fighter endured the second defeat of his 28-fight career.
The Champion Secures Triumph in Dull Affair
His career development has slowed in the past few years through promotional disputes and extended periods of inactivity.
Once tipped as the next star of the British fight scene, he now finds himself trying to fulfil that early promise - possibly in what seems like a last chance - under recent support.
He opened tentatively, with the two boxers ready to be aggressive in a cagey early stages.
Parker, whose single earlier setback came at super-middleweight against his former opponent in two years ago after damaging his hand mid-fight, was participating in his second bout at light heavyweight.
By the fight's midpoint, Parker had kept it close, making life awkward for the favorite, who worked behind a solid defense to edge the cleaner rounds.
The crowd's patience wore thin because of frequent holding, with the challenger falling to the floor multiple occasions during grappling.
The underdog finished the stronger, but many rounds were difficult to score. However, former world champion the boxing analyst - providing analysis for Dazn - had it significantly in favor for Parker, giving Buatsi just one round.
The victor moves on, but with the presence of hard hitter David Benavidez, and Russian star Dmitry Bivol dominating the weight class, the road to world glory - judging by this showing - still seems difficult.
Ricky Hatton Tribute Inspires All-Manchester Fight
In the secondary fight, Arthur beat Bradley Rea by divided decision in a terrific Manchester vs Manchester contest to capture the European light heavyweight belt.
The arena grew hushed for a profoundly moving memorial prior to the bout as 10 bells tolled in honor of Manchester's own Hatton, who died 46 years old in recently.
It was the initial significant broadcast fight night in the location since Hatton's passing. As the concluding sound faded, the stillness gave way to a roar of "only one Hatton".
The fighting within the ring reflected the emotion. Arthur was sent to the canvas by a left hook flush on the chin in the early round, standing uncertainly to his footing on the count of eight.
But the traditional red attire of the fighter soon came forward again. From the other corner, Rea - in opposing blue - was damaged early, heavy swelling developing under his eye as the duo exchanged hard punches.
Rea, 27, connected with strong blows but the champion, 34, responded in kind with powerful upward punches as the action hardly diminished over twelve rounds.
Arthur barely secured the result with judges scorecards of even score, 115-113 and 115-112, but the two athletes were determined and brave, everything their hero the legend stood for.
