British light-heavyweight Buatsi made a winning yet disappointing beginning to his career under recent management with a unanimous decision over Zach Parker in Manchester.
The Olympic bronze medallist's activity level likely gained him a judges' verdict in a tight ten-round bout at the Manchester venue.
But the challenger found success, landing some telling clean blows in a contest where the techniques never quite clicked, with constant grabbing marring the contest.
The scoring judges scored it 96-94 for to Buatsi, with the final judge a 95-95.
"It wasn't my best display but what defines champions? They prevail," Buatsi stated in the ring as he was faced boos from the spectators.
The British fighter bounced back after his initial pro loss - an epic battle with his previous opponent in February - to secure a twentieth professional win.
Various analysts felt Parker, thirty-one, should have been awarded the decision but the Derbyshire fighter experienced the second setback of his 28-fight career.
The Champion Claims Victory in Uneventful Encounter
The fighter's advancement has plateaued in the past few years through promotional disputes and considerable time of inactivity.
Previously predicted as the rising talent of UK boxing, he now stands trying to fulfil that early promise - possibly in what appears to be a last chance - under new promotional backing.
He started carefully, with the two boxers ready to be aggressive in a cagey early stages.
The challenger, whose single earlier setback came at super-middleweight against his former opponent in 2022 after damaging his hand in the contest, was competing in only his second bout at the higher weight class.
By the halfway stage, the underdog had made it competitive, causing problems for Buatsi, who worked behind a protective stance to barely take the better stanzas.
The audience's tolerance wore thin during regular grabbing, with Parker falling to the floor multiple occasions during grappling.
The underdog ended stronger, but several stanzas were difficult to score. However, previous titleholder the boxing analyst - working with the broadcast network - had it significantly in favor for the challenger, giving Buatsi just only one stanza.
The victor moves on, 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 appears challenging.
Ricky Hatton Tribute Fuels All-Manchester Fight
In the co-main event, Arthur beat Bradley Rea by split-decision in a outstanding local rivalry contest to secure the European light-heavyweight belt.
The stadium grew hushed for a profoundly moving homage before the fight as 10 bells rang in memory of local hero Hatton, who succumbed at age 46 in September.
It was the first major televised match card in the city since Hatton's death. As the concluding sound faded, the quiet gave way to a shout of "there's only one Ricky Hatton".
The fighting during the bout matched the feeling. The eventual winner was floored by a significant blow directly to the chin in the second round, standing uncertainly to his feet on the eight count.
But the red-colored shorts of the fighter soon advanced again. On the opposite side, Rea - in competitive blue - was marked up early, significant bruising appearing under his orbital area as the duo exchanged hard punches.
The challenger, twenty-seven, landed power punches but Arthur, 34, responded in kind with powerful upward punches as the intensity hardly diminished over 12 rounds.
Arthur barely secured the decision with scoring tallies of even score, 115-113 and 115-112, but both fighters were determined and brave, all the qualities their hero the legend stood for.
