British light heavyweight Buatsi earned a win yet unimpressive start to life under new promoters with a points victory over Zach Parker in the Manchester arena.
The Olympic medal winner's work rate appeared to earn him a judges' verdict in a close 10-round contest at the Co-op Live Arena.
But Parker landed significant shots, landing some telling clean blows in a match where the techniques didn't complement each other, with constant grabbing disrupting the action.
Two judges had it 96-94 in favor to the winner, with the final judge a 95-95.
"It wasn't my greatest performance but what do champions do? They succeed," Buatsi commented in the arena as he was greeted with boos from the crowd.
The British fighter returned to winning ways after his initial pro loss - an epic battle with Callum Smith in last winter - to claim a twentieth professional win.
Several boxing experts believed the challenger, thirty-one, merited the decision but the Derbyshire fighter suffered the second defeat of his 28-fight professional journey.
The Champion Claims Victory in Dull Affair
Buatsi's progress has stalled in recent years through promotional disputes 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 - maybe in what seems like a final roll of the dice - under new promotional backing.
He began cautiously, with neither fighter ready to take risks in a cagey early stages.
Parker, whose single earlier setback came at super middleweight against his former opponent in 2022 after breaking his hand during the bout, was participating in his second fight at the higher weight class.
By the fight's midpoint, the underdog had kept it close, creating difficulties for Buatsi, who utilized a solid defense to narrowly win the more effective rounds.
The spectators' acceptance decreased because of frequent holding, with Parker falling to the floor multiple occasions during close exchanges.
Parker ended stronger, but multiple periods were challenging to assess. Although, former world champion Carl Frampton - commentating on the broadcast network - had it significantly in favor for the challenger, awarding Buatsi just only one stanza.
The victor advances, but with the presence of hard hitter Benavidez, and Eastern European fighter Bivol ruling the division, the road to world glory - based on this performance - still appears challenging.
Hatton Homage Motivates All-Manchester Contest
In the secondary fight, Lyndon Arthur beat Rea by split-decision in a outstanding Manchester vs Manchester fight to secure the European light-heavyweight title.
The stadium became quiet for a extremely emotional homage before the fight as 10 bells rang in remembrance of local hero Hatton, who succumbed 46 years old in September.
It was the first major televised match card in the location since Hatton's death. As the concluding sound disappeared, the silence transitioned to a roar of "there's just one Hatton".
The competition within the ring reflected the emotion. Arthur was knocked down by a powerful punch squarely on the chin in the second round, rising shakily to his position on the count of eight.
But the Manchester United-red attire of the fighter soon came forward again. On the opposite side, Rea - in opposing blue - was marked up quickly, significant bruising appearing under his orbital area as the pair traded punishing blows.
Rea, 27, connected with strong blows but Arthur, 34, matched the intensity with powerful upward punches as the pace rarely dropped over the full distance.
Arthur edged the decision with judges scorecards of even score, 115-113 and clearer margin, but each competitor were persistent and full of heart, exactly what their idol the legend embodied.
