British light heavyweight Buatsi earned a win yet unimpressive start to life under recent management with a unanimous decision over Zach Parker in Manchester.
The Olympic medal winner's activity level likely gained him a split decision in a competitive ten-round bout at the Manchester venue.
But the challenger found success, landing some telling clean blows in a fight where the styles failed to mesh, with constant grabbing marring the action.
Two judges judged it 96-94 to the winner, with the third a even score.
"It wasn't my best performance but what defines champions? They succeed," Buatsi said in the ringside as he was met by negative reactions from the audience.
The British fighter got back to winning after his first professional defeat - an memorable fight with Callum Smith in last winter - to earn a 20th career victory.
Some ringside observers thought the challenger, 31, merited the decision but the Derbyshire fighter experienced the second defeat of his 28-bout professional journey.
The Champion Secures Victory in Uneventful Encounter
Buatsi's progress has plateaued in recent times through promotional disputes and considerable time of lack of fights.
Once tipped as the next star of British boxing, he now finds himself trying to achieve expectations - perhaps in what appears to be a ultimate opportunity - under new promotional backing.
He opened tentatively, with the two boxers prepared to take risks in a cagey opening few rounds.
Parker, whose only previous defeat came at super middleweight against John Ryder in two years ago after breaking his hand during the bout, was participating in his second fight at the higher weight class.
By the halfway stage, Parker had kept it close, making life awkward for the favorite, who worked behind a tight guard to edge the better periods.
The spectators' acceptance diminished amid constant clinching, with Parker falling to the floor multiple occasions during grappling.
Parker finished the stronger, but multiple periods were difficult to score. However, ex-champion Carl Frampton - commentating on the broadcast network - had it significantly in favor for the challenger, scoring for Buatsi just one round.
The victor progresses, but with the presence of heavy hitter David Benavidez, and Eastern European fighter Bivol ruling the division, the road to world glory - judging by this showing - still seems difficult.
Hatton Memorial Motivates Local Rivalry Fight
In the co-main event, Lyndon Arthur defeated Bradley Rea by close verdict in a terrific Manchester vs Manchester fight to secure the continental title.
The arena fell silent for a deeply poignant memorial prior to the bout as ten bells tolled in honor of local hero Hatton, who succumbed aged 46 in last month.
It was the initial significant broadcast match card in the city since the passing of Hatton. As the concluding sound disappeared, the silence gave way to a chant of "there's only one Ricky Hatton".
The action within the ring equaled the sentiment. Arthur was floored by a powerful punch flush on the chin in the second round, getting up unsteadily to his feet on the count of eight.
But the red-colored equipment of Arthur soon came forward again. From the other corner, Rea - in opposing blue - was injured soon, heavy swelling developing under his orbital area as the fighters landed powerful shots.
The challenger, twenty-seven, connected with strong blows but the champion, thirty-four, matched the intensity with stinging uppercuts as the action rarely dropped over twelve rounds.
Arthur edged the verdict with official scores of 114-114, narrow lead and 115-112, but the two athletes were persistent and full of heart, all the qualities their hero the legend represented.
