UK light-heavyweight Buatsi secured a victory yet unimpressive debut to his career under fresh promotional backing with a points victory over Zach Parker in Manchester.
The Olympic medal winner's work rate seemingly secured him a judges' verdict in a close ten-round bout at the Manchester venue.
But Parker had his moments, landing some telling single shots in a fight where the techniques failed to mesh, with constant grabbing spoiling the fight.
The officials scored it 96-94 in favor to Buatsi, with the remaining official a even score.
"It wasn't my finest performance but what do champions do? They win," Buatsi said in the ringside as he was greeted with disapproval from the crowd.
The British fighter returned to winning ways after his maiden career setback - an memorable fight with Callum Smith in last winter - to earn a twentieth professional win.
Some ringside observers felt the challenger, thirty-one, deserved the decision but the Derbyshire fighter experienced the second setback of his 28-match professional journey.
Buatsi Secures Victory in Dull Match
His career development has stalled in recent times through management issues and considerable time of lack of fights.
Earlier forecast as the future of British boxing, he now stands trying to achieve expectations - possibly in what seems like a final roll of the dice - under new promotional backing.
He opened tentatively, with both competitors willing to take risks in a tentative initial rounds.
The challenger, whose single earlier setback came at the lower weight class against his former opponent in two years ago after breaking his hand in the contest, was competing in only his second appearance at light-heavyweight.
By the middle rounds, the underdog had kept it close, creating difficulties for the favorite, who utilized a protective stance to edge the more effective rounds.
The audience's tolerance diminished during regular grabbing, with the challenger falling to the floor several times during close exchanges.
Parker closed well, but several stanzas were challenging to assess. Although, ex-champion the boxing analyst - commentating on Dazn - had it strongly leaning for Parker, scoring for Buatsi just only one stanza.
The victor progresses, but with the caliber of power puncher David Benavidez, and Russian star Dmitry Bivol dominating the weight class, the journey to titles - on this evidence - still looks steep.
Hatton Memorial Motivates All-Manchester Contest
In the supporting bout, Lyndon Arthur defeated Bradley Rea by split-decision in a outstanding Manchester vs Manchester contest to secure the European light heavyweight belt.
The arena became quiet for a extremely emotional homage prior to the bout as a bell ceremony sounded in honor of local hero Ricky Hatton, who passed away at age 46 in last month.
It was the premier televised boxing event in the urban center since Hatton's death. As the concluding sound disappeared, the stillness gave way to a roar of "there's just one Ricky Hatton".
The fighting within the ring equaled the emotion. The eventual winner was floored by a left hook directly to the face in the early round, getting up unsteadily to his footing on the referee's count.
But the Manchester United-red attire of Arthur soon came forward again. From the other corner, the opponent - in opposing blue - was damaged soon, heavy swelling appearing under his eye as the duo landed hard punches.
Rea, 27, delivered effective strikes but Arthur, thirty-four, matched the intensity with effective uppercuts as the intensity rarely dropped over the full distance.
The victor edged the result with official scores of 114-114, close margin and 115-112, but both fighters were determined and courageous, all the qualities their idol Hatton embodied.
