British light heavyweight Buatsi secured a victory yet underwhelming start to his career under fresh promotional backing with a decision win over Zach Parker in the Manchester arena.
The Olympic medal winner's activity level appeared to earn him a split decision in a tight 10-round fight at the boxing arena.
But Parker landed significant shots, delivering effective single shots in a fight where the approaches didn't complement each other, with constant grabbing spoiling the fight.
The officials judged it 96-94 in favor to the winner, with the remaining official a 95-95.
"It wasn't my greatest showing but what defines champions? They succeed," Buatsi stated in the arena as he was greeted with disapproval from the spectators.
The Londoner returned to winning ways after his initial pro loss - an epic battle with his previous opponent in February - to claim a 20th career victory.
Several boxing experts felt the challenger, thirty-one, merited the win but the British boxer experienced the second setback of his 28-match career.
The Champion Secures Win in Dull Encounter
Buatsi's progress has stalled in the past few years through contract problems and considerable time of inactivity.
Previously predicted as the future of UK boxing, he now is positioned trying to realize his potential - possibly in what appears to be a final roll of the dice - under recent support.
He opened tentatively, with both competitors prepared to take risks in a calculated initial rounds.
The challenger, whose single earlier setback came at super-middleweight against John Ryder in 2022 after damaging his hand in the contest, was participating in his second appearance at light-heavyweight.
By the fight's midpoint, the underdog had kept it close, causing problems for the favorite, who utilized a protective stance to narrowly win the cleaner stanzas.
The crowd's patience diminished during constant clinching, with Parker going down several times during close exchanges.
The underdog finished the stronger, but many rounds were hard to judge. Although, ex-champion the boxing analyst - commentating on the broadcast network - had it strongly leaning for the challenger, scoring for Buatsi just only one stanza.
Buatsi moves on, but with the likes of power puncher Benavidez, and Russian star Bivol ruling the division, the journey to titles - judging by this showing - still looks steep.
Hatton Tribute Inspires Manchester Derby Battle
In the secondary fight, Arthur beat Bradley Rea by split-decision in a terrific all-Manchester battle to capture the continental championship.
The venue became quiet for a deeply poignant memorial before the fight as ten bells tolled in remembrance of the city's native Hatton, who passed away aged 46 in recently.
It was the initial significant broadcast fight night in the urban center since Hatton's passing. As the last bell disappeared, the silence gave way to a roar of "there's only one Hatton".
The competition inside the ropes equaled the emotion. The eventual winner was floored by a left hook directly to the jaw in the early round, getting up unsteadily to his feet on the eight count.
But the traditional red shorts of the fighter soon pressed ahead again. Across the ring, the opponent - in opposing blue - was marked up early, noticeable damage developing under his face as the fighters landed hard punches.
Rea, 27, delivered effective strikes but Arthur, thirty-four, fought fire with fire with effective uppercuts as the intensity seldom decreased over 12 rounds.
Arthur edged the result with judges scorecards of even score, 115-113 and clearer margin, but each competitor were persistent and brave, exactly what their hero Hatton embodied.
