British light heavyweight Buatsi secured a victory yet unimpressive debut to his career under new promoters with a unanimous decision over Zach Parker in Manchester.
The Olympic medal winner's activity level appeared to earn him a judges' verdict in a close 10-round fight at the Co-op Live Arena.
But the challenger had his moments, delivering effective individual punches in a fight where the styles never quite clicked, with excessive holding disrupting the contest.
The officials had it 96-94 for to Buatsi, with the third a even score.
"It wasn't my best showing but what do champions do? They prevail," Buatsi said in the ringside as he was faced negative reactions from the crowd.
The British fighter returned to winning ways after his first professional defeat - an memorable fight with his previous opponent in last winter - to claim a twentieth professional win.
Several boxing experts felt the challenger, 31, deserved the decision but the British boxer endured the second loss of his 28-fight career.
The Champion Earns Victory in Dull Affair
His career development has slowed in the past few years through contract problems and considerable time of lack of fights.
Once tipped as the rising talent of UK boxing, he now finds himself trying to realize his potential - perhaps in what feels like a final roll of the dice - under new promotional backing.
He opened tentatively, with neither fighter prepared to overcommit in a tentative early stages.
The challenger, whose sole prior loss came at the lower weight class against his former opponent in two years ago after damaging his hand mid-fight, was competing in only his second fight at light heavyweight.
By the fight's midpoint, Parker had made it competitive, creating difficulties for the favorite, who worked behind a protective stance to narrowly win the more effective rounds.
The spectators' acceptance wore thin because of frequent holding, with the challenger falling to the floor various instances during clinches.
Parker finished the stronger, but multiple periods were difficult to score. Although, previous titleholder Carl Frampton - working with the broadcast network - had it significantly in favor for Parker, scoring for Buatsi just only one stanza.
Buatsi advances, but with the caliber of heavy hitter David Benavidez, and Russian star Bivol dominating the weight class, the journey to titles - on this evidence - still appears challenging.
Hatton Tribute Motivates All-Manchester Contest
In the supporting bout, Arthur overcame Bradley Rea by divided decision in a outstanding all-Manchester fight to secure the continental championship.
The venue fell silent for a extremely emotional homage ahead of the contest as 10 bells rang in honor of Manchester's own Hatton, who succumbed aged 46 in September.
It was the first major televised match card in the city since Hatton's death. As the concluding sound ended, the stillness transitioned to a shout of "there's only one Ricky Hatton".
The competition within the ring equaled the emotion. The eventual winner was floored by a significant blow squarely on the jaw in the early round, standing uncertainly to his feet on the eight count.
But the traditional red shorts of Arthur soon pressed ahead again. On the opposite side, Rea - in opposing blue - was damaged soon, heavy swelling appearing under his orbital area as the duo traded hard punches.
Rea, twenty-seven, connected with strong blows but Arthur, 34, responded in kind with effective uppercuts as the intensity hardly diminished over twelve rounds.
The victor barely secured the result with judges scorecards of even score, narrow lead and clearer margin, but each competitor were persistent and brave, everything their inspiration Hatton stood for.
