British light heavyweight Buatsi made a winning yet unimpressive beginning to life under fresh promotional backing with a points victory over Zach Parker in Manchester.
The Olympic bronze medallist's work rate seemingly secured him a split decision in a competitive 10-round fight at the Co-op Live Arena.
But the challenger landed significant shots, connecting with powerful individual punches in a match where the techniques never quite clicked, with constant grabbing disrupting the action.
The officials had it 96-94 for to Buatsi, with the remaining official a 95-95.
"It wasn't my greatest showing but what do champions do? They succeed," the victor commented in the arena as he was faced boos from the spectators.
The British fighter got back to winning after his initial pro loss - an memorable fight with his previous opponent in February - to secure a twentieth professional win.
Various analysts believed Parker, thirty-one, merited the win but the contender experienced the second loss of his 28-bout career.
The Champion Secures Triumph in Dull Encounter
His career development has slowed in recent years through management issues and extended periods of inactivity.
Previously predicted as the rising talent of the British fight scene, he now finds himself trying to fulfil that early promise - maybe in what seems like a last chance - under new promotional backing.
He began cautiously, with the two boxers ready to overcommit in a calculated initial rounds.
Parker, whose single earlier setback came at super middleweight against John Ryder in two years ago after suffering a hand injury mid-fight, was competing in only his second bout at light heavyweight.
By the halfway stage, Parker had made it competitive, creating difficulties for Buatsi, who operated with a protective stance to barely take the cleaner rounds.
The spectators' acceptance diminished because of frequent holding, with Parker falling to the floor multiple occasions during grappling.
The underdog closed well, but many rounds were difficult to score. Although, previous titleholder the boxing analyst - working with the broadcast network - had it strongly leaning for Parker, giving Buatsi just one round.
The victor advances, but with the likes of hard hitter Benavidez, and Russian star Bivol ruling the division, the path to championship success - based on this performance - still appears challenging.
Hatton Memorial Fuels Local Rivalry Fight
In the supporting bout, Arthur overcame Rea by divided decision in a terrific all-Manchester battle to win the continental title.
The arena fell silent for a deeply poignant memorial prior to the bout as ten bells sounded in honor of local hero Hatton, who died aged 46 in recently.
It was the premier televised fight night 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 fighting within the ring reflected the emotion. Arthur was floored by a left hook directly to the face in the early round, rising shakily to his footing on the count of eight.
But the traditional red shorts of Arthur soon advanced again. Across the ring, Rea - in competitive blue - was marked up soon, heavy swelling forming under his eye as the duo exchanged powerful shots.
Rea, twenty-seven, delivered effective strikes but Arthur, 34, responded in kind with powerful upward punches as the intensity rarely dropped over twelve rounds.
The victor barely secured the result with scoring tallies of even score, narrow lead and 115-112, but both fighters were determined and brave, everything their inspiration the legend represented.
