British light heavyweight Buatsi made a winning yet unimpressive beginning to life under fresh promotional backing with a points victory over Zach Parker in the Manchester arena.
The Olympic bronze medallist's activity level seemingly secured him a split decision in a close 10-round fight at the Manchester venue.
But Parker found success, delivering effective individual punches in a contest where the techniques didn't complement each other, with constant grabbing disrupting the fight.
The officials had it 96-94 in favor to Buatsi, with the remaining official a 95-95 draw.
"It wasn't my best performance but how do champions respond? They prevail," Buatsi stated in the arena as he was faced boos from the crowd.
The Londoner returned to winning ways after his maiden career setback - an epic battle with his previous opponent in last winter - to claim a 20th career victory.
Various analysts felt Parker, 31, deserved the victory but the contender suffered the second defeat of his 28-bout career.
Buatsi Secures Win in Slow Encounter
The fighter's advancement has stalled in the past few years through management issues and extended periods of inactivity.
Earlier forecast as the future of UK boxing, he now stands trying to fulfil that early promise - possibly in what seems like a ultimate opportunity - under new promotional backing.
He opened tentatively, with both competitors ready to take risks in a cagey initial rounds.
The challenger, whose only previous defeat came at super-middleweight against John Ryder in 2022 after damaging his hand during the bout, was participating in his second appearance at light-heavyweight.
By the middle rounds, Parker had kept it close, creating difficulties for the favorite, who operated with a protective stance to edge the cleaner stanzas.
The crowd's patience wore thin during regular grabbing, with the challenger going down various instances during close exchanges.
The underdog ended stronger, but several stanzas were hard to judge. Although, ex-champion Carl Frampton - providing analysis for Dazn - had it strongly leaning for the challenger, awarding Buatsi just only one stanza.
Buatsi moves on, but with the likes of hard hitter Benavidez, and Russian star Bivol ruling the division, the path to championship success - based on this performance - still looks steep.
Hatton Memorial Motivates Manchester Derby Fight
In the co-main event, Arthur beat Rea by split-decision in a terrific Manchester vs Manchester fight to secure the European light heavyweight championship.
The stadium became quiet for a profoundly moving homage before the fight as 10 bells rang in remembrance of local hero Hatton, who died at age 46 in September.
It was the premier televised boxing event in the location since Hatton's death. As the last bell disappeared, the silence became a chant of "there's only one Hatton".
The fighting within the ring matched the emotion. The eventual winner was floored by a left hook directly to the chin in the early round, standing uncertainly to his footing on the count of eight.
But the Manchester United-red equipment of Arthur soon pressed ahead again. On the opposite side, Rea - in competitive blue - was injured quickly, significant bruising forming under his face as the fighters landed hard punches.
The challenger, 27, delivered effective strikes but Arthur, thirty-four, responded in kind with effective uppercuts as the pace hardly diminished over 12 rounds.
The victor barely secured the result with judges scorecards of draw, 115-113 and wider gap, but each competitor were persistent and full of heart, all the qualities their hero the legend stood for.
