UK light heavyweight Buatsi secured a victory yet unimpressive beginning to life 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 judges' verdict in a close ten-round fight at the Co-op Live Arena.
But Parker found success, connecting with powerful individual punches in a contest where the styles never quite clicked, with frequent clinching disrupting the fight.
Two judges had it 96-94 for to Buatsi, with the remaining official a even score.
"It wasn't my best showing but how do champions respond? They win," the victor commented in the ringside as he was greeted with negative reactions from the crowd.
The British fighter returned to winning ways after his first professional defeat - an epic battle with his previous opponent in February - to secure a 20th career victory.
Several boxing experts believed Parker, thirty-one, merited the win but the British boxer suffered the second loss of his 28-match professional journey.
Buatsi Claims Victory in Slow Match
The fighter's advancement has slowed in recent times through contract problems and considerable time of lack of fights.
Previously predicted as the rising talent of the British fight scene, he now is positioned trying to fulfil that early promise - perhaps in what seems like a ultimate opportunity - under fresh management.
He opened tentatively, with the two boxers ready to take risks in a cagey opening few rounds.
The challenger, whose sole prior loss came at super middleweight against his former opponent in 2022 after suffering a hand injury mid-fight, was participating in his second bout at light heavyweight.
By the fight's midpoint, Parker had made it competitive, causing problems for the favorite, who utilized a solid defense to narrowly win the more effective stanzas.
The crowd's patience wore thin during constant clinching, with the challenger going down multiple occasions during clinches.
Parker closed well, but several stanzas were challenging to assess. However, former world champion the boxing analyst - providing analysis for Dazn - had it significantly in favor for Parker, scoring for Buatsi just one round.
Buatsi advances, but with the likes of heavy hitter David Benavidez, and Russian star Bivol leading the category, the road to world glory - on this evidence - still seems difficult.
Hatton Tribute Fuels Local Rivalry Battle
In the secondary fight, Arthur beat Bradley Rea by split-decision in a terrific all-Manchester contest to capture the European light heavyweight belt.
The venue fell silent for a profoundly moving tribute ahead of the contest as a bell ceremony tolled in remembrance of the city's native Ricky Hatton, who passed away at age 46 in September.
It was the premier televised fight night in the location since Hatton's death. As the concluding sound ended, the stillness became a shout of "only one Hatton".
The fighting during the bout equaled the feeling. Arthur was floored by a left hook flush on the jaw in the initial stage, getting up unsteadily to his feet on the referee's count.
But the red-colored equipment of the fighter soon advanced again. Across the ring, the opponent - in rival City blue - was injured soon, significant bruising developing under his eye as the fighters exchanged punishing blows.
The challenger, 27, delivered effective strikes but Arthur, 34, responded in kind with effective uppercuts as the pace hardly diminished over twelve rounds.
The victor barely secured the result with scoring tallies of draw, 115-113 and wider gap, but each competitor were persistent and courageous, exactly what their hero the legend represented.
