UK light heavyweight Buatsi earned a win yet disappointing start to life under fresh promotional backing with a decision win over Zach Parker in the Manchester arena.
The Olympic medal winner's work rate appeared to earn him a majority decision in a tight 10-round bout at the boxing arena.
But the challenger found success, landing some telling clean blows in a match where the styles never quite clicked, with frequent clinching disrupting the fight.
The officials had it 96-94 in favor to the winner, with the remaining official a 95-95.
"It wasn't my greatest showing but how do champions respond? They win," Buatsi said in the ringside as he was faced boos from the crowd.
The British fighter returned to winning ways after his maiden career setback - an thrilling contest with his previous opponent in February - to claim a 20th career victory.
Some ringside observers believed Parker, 31, merited the victory but the Derbyshire fighter experienced the second loss of his 28-match professional journey.
The Champion Claims Win in Dull Affair
His career development has slowed in the past few years through contract problems and considerable time of lack of fights.
Earlier forecast as the future of British boxing, he now finds himself trying to realize his potential - possibly in what feels like a ultimate opportunity - under recent support.
He started carefully, with neither fighter prepared to overcommit in a tentative opening few rounds.
Parker, whose sole prior loss came at the lower weight class against his former opponent in two years ago after damaging his hand during the bout, was competing in only his second appearance at light heavyweight.
By the middle rounds, the underdog had made it competitive, making life awkward for the favorite, who worked behind a tight guard to barely take the more effective periods.
The spectators' acceptance wore thin during constant clinching, with the challenger falling to the floor several times during grappling.
Parker closed well, but many rounds were challenging to assess. However, former world champion the boxing analyst - providing analysis for the broadcast network - had it significantly in favor for Parker, giving Buatsi just a single round.
Buatsi moves on, but with the presence of heavy hitter David Benavidez, and Eastern European fighter Bivol dominating the weight class, the journey to titles - on this evidence - still seems difficult.
Hatton Tribute Motivates All-Manchester Fight
In the supporting bout, Lyndon Arthur defeated Bradley Rea by split-decision in a excellent all-Manchester battle to capture the European light heavyweight belt.
The arena grew hushed for a extremely emotional tribute ahead of the contest as ten bells tolled in honor of Manchester's own Hatton, who passed away aged 46 in September.
It was the initial significant broadcast match card in the location since Hatton's passing. As the final chime ended, the silence transitioned to a roar of "there's just one Ricky Hatton".
The competition inside the ropes equaled the emotion. Arthur was sent to the canvas by a left hook flush on the face in the initial stage, rising shakily to his position on the count of eight.
But the Manchester United-red attire of Arthur soon advanced again. On the opposite side, the opponent - in opposing blue - was damaged quickly, noticeable damage developing under his face as the pair exchanged powerful shots.
Rea, twenty-seven, connected with strong blows but Arthur, thirty-four, matched the intensity with powerful upward punches as the action seldom decreased over 12 rounds.
Arthur barely secured the decision with official scores of even score, narrow lead and clearer margin, but both fighters were relentless and full of heart, exactly what their idol the legend represented.
