UK light heavyweight Buatsi made a winning yet unimpressive beginning to his career under new promoters with a decision win over Zach Parker in Manchester.
The Olympic medal winner's activity level appeared to earn him a split decision in a tight 10-round contest at the boxing arena.
But the challenger had his moments, delivering effective single shots in a fight where the approaches failed to mesh, with frequent clinching disrupting the fight.
Two judges judged it 96-94 in favor to Buatsi, with the remaining official a 95-95.
"It wasn't my greatest display but what defines champions? They succeed," Buatsi stated in the arena as he was faced negative reactions from the spectators.
The British fighter bounced back after his initial pro loss - an memorable fight with his previous opponent in last winter - to secure a 20th pro success.
Some ringside observers felt Parker, thirty-one, deserved the win but the Derbyshire fighter endured the second loss of his 28-bout career.
Buatsi Secures Victory in Slow Affair
The fighter's advancement has plateaued in recent years through contract problems and considerable time of inactivity.
Previously predicted as the future of the British fight scene, he now finds himself trying to achieve expectations - possibly in what seems like a ultimate opportunity - under recent support.
He began cautiously, with the two boxers willing to take risks in a cagey opening few rounds.
The challenger, whose sole prior loss came at the lower weight class 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 halfway stage, the underdog had made it competitive, causing problems for the favorite, who operated with a tight guard to barely take the cleaner stanzas.
The audience's tolerance decreased during regular grabbing, with the challenger falling to the floor multiple occasions during grappling.
The underdog ended stronger, but multiple periods were hard to judge. Nevertheless, ex-champion the boxing analyst - working with Dazn - had it strongly leaning for the challenger, awarding Buatsi just a single round.
Buatsi advances, but with the likes of power puncher David Benavidez, and Russian star Bivol leading the category, the path to championship success - based on this performance - still seems difficult.
Hatton Tribute Motivates Manchester Derby Battle
In the secondary fight, Arthur beat Bradley Rea by divided decision in a excellent Manchester vs Manchester contest to capture the European light heavyweight title.
The stadium became quiet for a profoundly moving homage prior to the bout as 10 bells sounded in honor of the city's native Hatton, who succumbed at age 46 in recently.
It was the first major televised match card in the location since the passing of Hatton. As the last bell disappeared, the quiet became a shout of "there's only one Ricky Hatton".
The action during the bout equaled the sentiment. The eventual winner was floored by a significant blow directly to the chin in the initial stage, rising shakily to his feet on the count of eight.
But the traditional red shorts of the fighter soon came forward again. On the opposite side, Rea - in opposing blue - was marked up quickly, noticeable damage forming under his face as the duo landed hard punches.
Rea, twenty-seven, landed power punches but Arthur, 34, fought fire with fire with effective uppercuts as the pace seldom decreased over 12 rounds.
Arthur narrowly won the result with scoring tallies of 114-114, close margin and 115-112, but the two athletes were relentless and courageous, exactly what their idol Hatton stood for.
