UK light heavyweight Buatsi made a winning yet underwhelming beginning to life under recent management with a unanimous decision over Zach Parker in the Manchester arena.
The Olympic bronze medallist's punch output likely gained him a split decision in a competitive 10-round fight at the Manchester venue.
But the challenger had his moments, landing some telling individual punches in a match where the techniques never quite clicked, with excessive holding disrupting the action.
The officials scored it 96-94 to Buatsi, with the remaining official a even score.
"It wasn't my finest showing but what do champions do? They prevail," Buatsi stated in the ringside as he was met by disapproval from the audience.
The British fighter bounced back after his first professional defeat - an memorable fight with Callum Smith in February - to secure a 20th career victory.
Some ringside observers felt the challenger, 31, should have been awarded the decision but the Derbyshire fighter experienced the second setback of his 28-match career.
The Champion Claims Win in Slow Match
His career development has stalled in recent times through management issues and long spells of lack of fights.
Previously predicted as the future of the British fight scene, he now stands trying to achieve expectations - possibly in what seems like a last chance - under recent support.
He opened tentatively, with neither fighter ready to be aggressive in a calculated early stages.
The challenger, whose sole prior loss came at the lower weight class against John Ryder in two years ago after breaking his hand during the bout, was making just his second fight at light-heavyweight.
By the halfway stage, Parker had stayed in contention, causing problems for Buatsi, who worked behind a protective stance to narrowly win the more effective rounds.
The audience's tolerance decreased during constant clinching, with the challenger slipping to the canvas various instances during close exchanges.
Parker closed well, but multiple periods were challenging to assess. However, former world champion the boxing analyst - commentating on Dazn - had it particularly wide for Parker, giving Buatsi just only one stanza.
Buatsi moves on, but with the likes of power puncher David Benavidez, and Russian champion Dmitry Bivol dominating the weight class, the journey to titles - based on this performance - still looks steep.
Hatton Tribute Inspires All-Manchester Battle
In the supporting bout, Arthur beat Bradley Rea by close verdict in a terrific Manchester vs Manchester contest to secure the European light-heavyweight championship.
The arena grew hushed for a deeply poignant tribute prior to the bout as a bell ceremony rang in honor of local hero Ricky Hatton, who succumbed at age 46 in September.
It was the initial significant broadcast boxing event in the urban center since Hatton's death. As the last bell disappeared, the silence transitioned to a shout of "only one Ricky Hatton".
The competition during the bout matched the feeling. The eventual winner was knocked down by a powerful punch flush on the face in the early round, getting up unsteadily to his position on the count of eight.
But the red-colored attire of the fighter soon pressed ahead again. From the other corner, Rea - in opposing blue - was damaged quickly, heavy swelling appearing under his eye as the pair landed powerful shots.
The challenger, 27, landed power punches but Arthur, 34, matched the intensity with effective uppercuts as the intensity rarely dropped over the full distance.
The victor narrowly won the decision with scoring tallies of even score, 115-113 and 115-112, but the two athletes were determined and courageous, all the qualities their idol the legend embodied.
