British light-heavyweight Buatsi earned a win yet unimpressive start to life under fresh promotional backing with a decision win over Zach Parker in the Manchester arena.
The Olympic bronze medallist's punch output appeared to earn him a split decision in a competitive ten-round bout at the boxing arena.
But Parker landed significant shots, connecting with powerful single shots in a match where the approaches didn't complement each other, with frequent clinching spoiling the fight.
Two judges scored it 96-94 in favor to the winner, with the third a 95-95 draw.
"It wasn't my best display but how do champions respond? They prevail," Buatsi commented in the ring as he was greeted with negative reactions from the crowd.
The Londoner bounced back after his initial pro loss - an thrilling contest with his previous opponent in February - to secure a 20th career victory.
Several boxing experts believed Parker, 31, should have been awarded the win but the British boxer experienced the second defeat of his 28-bout professional journey.
The Champion Earns Victory in Dull Affair
Buatsi's progress has plateaued in recent times through promotional disputes and extended periods of inactivity.
Earlier forecast as the future of the British fight scene, he now is positioned trying to fulfil that early promise - perhaps in what seems like a final roll of the dice - under fresh management.
He began cautiously, with the two boxers ready to take risks in a tentative initial rounds.
Parker, whose only previous defeat came at the lower weight class against John Ryder in 2022 after breaking his hand during the bout, was making just his second fight at the higher weight class.
By the halfway stage, Parker had made it competitive, creating difficulties for Buatsi, who operated with a protective stance to narrowly win the cleaner rounds.
The crowd's patience diminished because of frequent holding, with the challenger slipping to the canvas multiple occasions during clinches.
Parker finished the stronger, but several stanzas were difficult to score. However, ex-champion the boxing analyst - working with Dazn - had it strongly leaning for the challenger, awarding Buatsi just a single round.
The victor advances, but with the presence of heavy hitter Benavidez, and Eastern European fighter Dmitry Bivol dominating the weight class, the path to championship success - based on this performance - still seems difficult.
Hatton Memorial Motivates Local Rivalry Contest
In the co-main event, Arthur beat Bradley Rea by close verdict in a outstanding local rivalry contest to secure the continental title.
The arena became quiet for a extremely emotional tribute ahead of the contest as ten bells tolled in memory of local hero Ricky Hatton, who died aged 46 in September.
It was the first major televised match card in the urban center since the passing of Hatton. As the last bell disappeared, the silence became a roar of "there's only one Hatton".
The competition during the bout equaled the feeling. Arthur was knocked down by a significant blow flush on the face in the early round, getting up unsteadily to his feet on the referee's count.
But the traditional red equipment of the fighter soon advanced again. Across the ring, Rea - in competitive blue - was injured soon, noticeable damage forming under his eye as the duo exchanged powerful shots.
The challenger, twenty-seven, landed power punches but Arthur, 34, fought fire with fire with effective uppercuts as the action seldom decreased over the full distance.
The victor narrowly won the result with judges scorecards of 114-114, narrow lead and clearer margin, but the two athletes were persistent and courageous, exactly what their inspiration the legend represented.
