UK light-heavyweight Buatsi secured a victory yet underwhelming beginning to life under recent management with a points victory over Zach Parker in Manchester.
The Olympic medal winner's punch output likely gained him a split decision in a competitive 10-round bout at the Co-op Live Arena.
But Parker landed significant shots, delivering effective single shots in a contest where the approaches never quite clicked, with constant grabbing marring the contest.
The officials judged it 96-94 for to Buatsi, with the remaining official a even score.
"It wasn't my finest performance but what do champions do? They prevail," the victor said in the ring as he was faced disapproval from the audience.
The Londoner got back to winning after his maiden career setback - an memorable fight with his previous opponent in February - to earn a 20th career victory.
Various analysts believed the challenger, thirty-one, should have been awarded the win but the contender experienced the second loss of his 28-match professional journey.
Buatsi Claims Win in Uneventful Affair
Buatsi's progress has plateaued in recent years through management issues and extended periods of inactivity.
Once tipped as the rising talent of the British fight scene, he now is positioned trying to realize his potential - perhaps in what appears to be a final roll of the dice - under fresh management.
He started carefully, with both competitors willing to overcommit in a calculated initial rounds.
Parker, whose single earlier setback came at super-middleweight against John Ryder in 2022 after damaging his hand during the bout, was competing in only his second fight at light-heavyweight.
By the fight's midpoint, the underdog had kept it close, creating difficulties for Buatsi, who worked behind a protective stance to barely take the better periods.
The crowd's patience wore thin amid constant clinching, with the challenger going down several times during close exchanges.
The underdog ended stronger, but multiple periods were challenging to assess. However, former world champion the boxing analyst - working with Dazn - had it particularly wide for Parker, awarding Buatsi just a single round.
Buatsi advances, but with the likes of hard hitter David Benavidez, and Eastern European fighter Bivol ruling the division, the path to championship success - based on this performance - still seems difficult.
Hatton Homage Motivates Manchester Derby Battle
In the co-main event, Arthur overcame Bradley Rea by divided decision in a terrific Manchester vs Manchester contest to capture the European light heavyweight championship.
The arena fell silent for a profoundly moving memorial before the fight as a bell ceremony tolled in honor of the city's native Hatton, who passed away aged 46 in recently.
It was the premier televised fight night in the city since Hatton's passing. As the last bell disappeared, the silence became a roar of "there's just one Ricky Hatton".
The action within the ring equaled the feeling. Arthur was sent to the canvas by a significant blow squarely on the face in the second round, getting up unsteadily to his footing on the referee's count.
But the traditional red shorts of the fighter soon pressed ahead again. On the opposite side, Rea - in rival City blue - was marked up quickly, noticeable damage developing under his orbital area as the duo landed powerful shots.
Rea, 27, landed power punches but Arthur, 34, matched the intensity with effective uppercuts as the pace rarely dropped over the full distance.
The victor narrowly won the decision with official scores of 114-114, narrow lead and wider gap, but each competitor were relentless and brave, all the qualities their hero Hatton represented.
