British light heavyweight Buatsi earned a win yet unimpressive start to life under recent management with a points victory over Zach Parker in the Manchester arena.
The Olympic bronze medallist's punch output likely gained him a majority decision in a tight 10-round contest at the Manchester venue.
But Parker had his moments, landing some telling individual punches in a match where the styles didn't complement each other, with frequent clinching spoiling the contest.
Two judges had it 96-94 in favor to the winner, with the final judge a 95-95.
"It wasn't my best display but what defines champions? They prevail," Buatsi stated in the arena as he was met by negative reactions 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 secure a twentieth professional win.
Several boxing experts believed Parker, thirty-one, deserved the decision but the Derbyshire fighter experienced the second setback of his 28-fight career.
Buatsi Claims Win in Slow Affair
Buatsi's progress has plateaued in recent years through management issues and long spells of inactivity.
Earlier forecast as the future of UK boxing, he now stands trying to realize his potential - possibly in what feels like a final roll of the dice - under new promotional backing.
He opened tentatively, with neither fighter ready to overcommit in a cagey initial rounds.
The challenger, whose only previous defeat came at super-middleweight against his former opponent in 2022 after suffering a hand injury in the contest, was competing in only his second appearance at light heavyweight.
By the halfway stage, Parker had stayed in contention, causing problems for the favorite, who operated with a protective stance to narrowly win the more effective rounds.
The spectators' acceptance wore thin during regular grabbing, with the challenger falling to the floor various instances during clinches.
The underdog closed well, but multiple periods were difficult to score. However, previous titleholder the boxing analyst - providing analysis for the broadcast network - had it particularly wide for the challenger, scoring for Buatsi just one round.
Buatsi advances, but with the caliber of power puncher Benavidez, and Eastern European fighter Bivol leading the category, the journey to titles - on this evidence - still seems difficult.
Hatton Homage Motivates All-Manchester Contest
In the supporting bout, Arthur beat Rea by divided decision in a outstanding Manchester vs Manchester battle to win the European light-heavyweight belt.
The stadium fell silent for a extremely emotional tribute ahead of the contest as 10 bells rang in memory of Manchester's own Ricky Hatton, who died aged 46 in last month.
It was the premier televised boxing event in the city since Hatton's passing. As the last bell disappeared, the silence transitioned to a chant of "there's just one Hatton".
The competition inside the ropes reflected the sentiment. The eventual winner was knocked down by a left hook flush on the face in the initial stage, rising shakily to his position on the eight count.
But the red-colored shorts of the fighter soon advanced again. Across the ring, the opponent - in competitive blue - was marked up early, heavy swelling developing under his orbital area as the pair exchanged punishing blows.
The challenger, 27, landed power punches but Arthur, 34, responded in kind with stinging uppercuts as the intensity rarely dropped over the full distance.
The victor edged the result with scoring tallies of even score, 115-113 and 115-112, but the two athletes were persistent and brave, all the qualities their idol the legend stood for.
