British light heavyweight Buatsi earned a win yet unimpressive debut to life under recent management with a unanimous decision over Zach Parker in Manchester.
The Olympic bronze medallist's activity level likely gained him a judges' verdict in a tight ten-round contest at the boxing arena.
But Parker found success, delivering effective clean blows in a fight where the techniques never quite clicked, with constant grabbing spoiling the contest.
The officials had it 96-94 for to Buatsi, with the remaining official a even score.
"It wasn't my finest showing but how do champions respond? They succeed," Buatsi stated in the ring as he was faced disapproval from the spectators.
The British fighter returned to winning ways after his maiden career setback - an memorable fight with Callum Smith in last winter - to earn a 20th career victory.
Various analysts thought the challenger, thirty-one, should have been awarded the decision but the contender experienced the second loss of his 28-match professional journey.
The Champion Secures Win in Slow Affair
The fighter's advancement has slowed in recent years through promotional disputes and extended periods of lack of fights.
Previously predicted as the rising talent of the British fight scene, he now finds himself trying to fulfil that early promise - perhaps in what feels like a last chance - under fresh management.
He began cautiously, with the two boxers ready to be aggressive in a tentative early stages.
The challenger, whose single earlier setback came at super middleweight against his former opponent in 2022 after breaking his hand in the contest, was participating in his second fight at the higher weight class.
By the halfway stage, the underdog had stayed in contention, creating difficulties for Buatsi, who utilized a tight guard to barely take the cleaner periods.
The audience's tolerance wore thin amid frequent holding, with Parker going down multiple occasions during grappling.
The underdog finished the stronger, but several stanzas were challenging to assess. Although, previous titleholder the boxing analyst - working with Dazn - had it strongly leaning for the challenger, scoring for Buatsi just a single round.
Buatsi moves on, but with the likes of power puncher Benavidez, and Russian star Bivol dominating the weight class, the road to world glory - judging by this showing - still appears challenging.
Ricky Hatton Memorial Fuels Local Rivalry Contest
In the co-main event, Arthur overcame Bradley Rea by divided decision in a outstanding local rivalry fight to secure the continental belt.
The venue became quiet for a deeply poignant memorial prior to the bout as a bell ceremony rang in honor of Manchester's own Hatton, who passed away 46 years old in recently.
It was the premier televised fight night in the location since Hatton's passing. As the last bell ended, the silence gave way to a roar of "only one Ricky Hatton".
The fighting within the ring equaled the feeling. The eventual winner was sent to the canvas by a significant blow directly to the jaw in the early round, standing uncertainly to his feet on the referee's count.
But the traditional red attire of Arthur soon came forward again. On the opposite side, the opponent - in competitive blue - was injured soon, heavy swelling developing under his face as the fighters landed hard punches.
The challenger, 27, landed power punches but the champion, thirty-four, fought fire with fire with effective uppercuts as the action rarely dropped over the full distance.
Arthur barely secured the result with scoring tallies of even score, 115-113 and clearer margin, but both fighters were persistent and courageous, exactly what their inspiration the legend embodied.
