British light-heavyweight Buatsi earned a win yet disappointing debut to his career under recent management with a points victory over Zach Parker in the Manchester arena.
The Olympic medal winner's punch output seemingly secured him a split decision in a close ten-round fight at the Co-op Live Arena.
But the challenger found success, delivering effective individual punches in a match where the styles never quite clicked, with frequent clinching disrupting the fight.
Two judges scored it 96-94 to the winner, with the third a 95-95.
"It wasn't my greatest display but what defines champions? They succeed," Buatsi stated in the ringside as he was greeted with disapproval from the audience.
The Londoner got back to winning after his initial pro loss - an memorable fight with his previous opponent in February - to earn a 20th pro success.
Some ringside observers thought Parker, thirty-one, should have been awarded the decision but the Derbyshire fighter endured the second defeat of his 28-fight professional journey.
Buatsi Claims Win in Slow Encounter
The fighter's advancement has slowed in the past few years through contract problems and considerable time of lack of fights.
Once tipped as the next star of British boxing, he now is positioned trying to fulfil that early promise - possibly in what feels like a final roll of the dice - under new promotional backing.
He began cautiously, with the two boxers willing to overcommit in a cagey opening few rounds.
Parker, whose sole prior loss came at super-middleweight against his former opponent in 2022 after breaking his hand in the contest, was making just his second fight at the higher weight class.
By the halfway stage, the underdog had stayed in contention, causing problems for the favorite, who operated with a solid defense to barely take the more effective periods.
The spectators' acceptance decreased amid frequent holding, with the challenger falling to the floor various instances during clinches.
Parker finished the stronger, but several stanzas were challenging to assess. However, ex-champion the boxing analyst - commentating on Dazn - had it strongly leaning for the challenger, giving Buatsi just only one stanza.
Buatsi moves on, but with the caliber of power puncher David Benavidez, and Russian star Dmitry Bivol dominating the weight class, the journey to titles - on this evidence - still appears challenging.
Ricky Hatton Memorial Inspires Local Rivalry Contest
In the co-main event, Arthur overcame Rea by close verdict in a outstanding local rivalry battle to secure the European light-heavyweight belt.
The venue fell silent for a deeply poignant tribute ahead of the contest as a bell ceremony rang in honor of local hero Hatton, who died 46 years old in September.
It was the premier televised match card in the urban center since Hatton's death. As the final chime faded, the quiet transitioned to a chant of "there's just one Ricky Hatton".
The competition during the bout reflected the sentiment. Arthur was floored by a powerful punch squarely on the chin in the early round, standing uncertainly to his position on the eight count.
But the red-colored shorts of the fighter soon came forward again. On the opposite side, the opponent - in competitive blue - was injured quickly, significant bruising developing under his eye as the pair traded punishing blows.
Rea, twenty-seven, delivered effective strikes but Arthur, thirty-four, fought fire with fire with powerful upward punches as the intensity seldom decreased over 12 rounds.
Arthur edged the result with scoring tallies of draw, 115-113 and wider gap, but each competitor were persistent and full of heart, exactly what their idol Hatton represented.
