British light-heavyweight Buatsi secured a victory yet underwhelming beginning to life under new promoters with a points victory over Zach Parker in Manchester.
The Olympic bronze medallist's punch output seemingly secured him a split decision in a competitive ten-round fight at the Manchester venue.
But Parker had his moments, connecting with powerful single shots in a match where the techniques failed to mesh, with excessive holding spoiling the contest.
The officials had it 96-94 to the winner, with the remaining official a even score.
"It wasn't my greatest showing but how do champions respond? They succeed," Buatsi commented in the arena as he was greeted with boos from the spectators.
The British fighter got back to winning after his first professional defeat - an memorable fight with his previous opponent in last winter - to claim a 20th pro success.
Various analysts felt Parker, 31, should have been awarded the victory but the contender suffered the second defeat of his 28-match professional journey.
Buatsi Secures Win in Slow Affair
His career development has slowed in the past few years through contract problems and long spells of inactivity.
Once tipped as the next star of British boxing, he now is positioned trying to realize his potential - possibly in what seems like a final roll of the dice - under recent support.
He opened tentatively, with both competitors ready to overcommit in a tentative early stages.
The challenger, whose only previous defeat came at the lower weight class against John Ryder in 2022 after damaging his hand during the bout, was participating in his second appearance at the higher weight class.
By the halfway stage, Parker had kept it close, causing problems for Buatsi, who utilized a protective stance to edge the better periods.
The audience's tolerance wore thin because of regular grabbing, with Parker going down several times during clinches.
Parker closed well, but multiple periods were hard to judge. However, previous titleholder Carl Frampton - commentating on the broadcast network - had it strongly leaning for the challenger, giving Buatsi just a single round.
Buatsi progresses, but with the likes of hard hitter David Benavidez, and Eastern European fighter Bivol ruling the division, the road to world glory - judging by this showing - still looks steep.
Ricky Hatton Homage Motivates Local Rivalry Contest
In the supporting bout, Arthur overcame Bradley Rea by divided decision in a outstanding Manchester vs Manchester fight to win the European light heavyweight title.
The arena grew hushed for a deeply poignant tribute ahead of the contest as 10 bells sounded in remembrance of Manchester's own Ricky Hatton, who succumbed 46 years old in September.
It was the premier televised match card in the city since Hatton's death. As the final chime ended, the quiet transitioned to a chant of "there's only one Ricky Hatton".
The action within the ring equaled the sentiment. The eventual winner was floored by a significant blow directly to the face in the early round, rising shakily to his footing on the count of eight.
But the red-colored shorts of Arthur soon advanced again. Across the ring, Rea - in competitive blue - was marked up early, heavy swelling appearing under his eye as the fighters landed hard punches.
Rea, twenty-seven, connected with strong blows but Arthur, thirty-four, responded in kind with powerful upward punches as the action rarely dropped over 12 rounds.
Arthur narrowly won the result with judges scorecards of 114-114, 115-113 and 115-112, but both fighters were determined and full of heart, everything their hero the legend represented.
