UK light heavyweight Buatsi earned a win yet unimpressive beginning to life under fresh promotional backing with a decision win over Zach Parker in Manchester.
The Olympic bronze medallist's work rate seemingly secured him a judges' verdict in a tight ten-round contest at the boxing arena.
But the challenger found success, delivering effective individual punches in a fight where the approaches failed to mesh, with constant grabbing disrupting the action.
The officials judged it 96-94 for to Buatsi, with the final judge a even score.
"It wasn't my finest showing but what do champions do? They win," the victor said in the ringside as he was greeted with negative reactions from the spectators.
The Londoner returned to winning ways after his first professional defeat - an memorable fight with Callum Smith in February - to secure a 20th career victory.
Some ringside observers felt the challenger, thirty-one, should have been awarded the victory but the Derbyshire fighter experienced the second loss of his 28-bout career.
Buatsi Earns Victory in Dull Match
The fighter's advancement has plateaued in recent years through contract problems and considerable time of inactivity.
Earlier forecast as the rising talent of UK boxing, he now finds himself trying to achieve expectations - maybe in what seems like a last chance - under recent support.
He opened tentatively, with the two boxers prepared to overcommit in a tentative opening few rounds.
Parker, whose only previous defeat came at the lower weight class against his former opponent in 2022 after damaging his hand mid-fight, was participating in his second appearance at light heavyweight.
By the middle rounds, Parker had stayed in contention, creating difficulties for the favorite, who utilized a solid defense to narrowly win the cleaner periods.
The spectators' acceptance wore thin during constant clinching, with Parker slipping to the canvas various instances during grappling.
Parker ended stronger, but several stanzas were hard to judge. Nevertheless, ex-champion the boxing analyst - commentating on the broadcast network - had it particularly wide for Parker, awarding Buatsi just one round.
Buatsi moves on, but with the caliber of power puncher David Benavidez, and Russian champion Dmitry Bivol ruling the division, the path to championship success - judging by this showing - still seems difficult.
Hatton Tribute Fuels Manchester Derby Battle
In the supporting bout, Lyndon Arthur beat Bradley Rea by split-decision in a excellent all-Manchester fight to capture the continental title.
The stadium fell silent for a extremely emotional memorial ahead of the contest as a bell ceremony sounded in honor of the city's native Hatton, who passed away at age 46 in recently.
It was the premier televised fight night in the city since Hatton's passing. As the final chime disappeared, the silence gave way to a chant of "there's just one Ricky Hatton".
The fighting during the bout reflected the emotion. Arthur was floored by a left hook squarely on the jaw in the initial stage, rising shakily to his feet on the referee's count.
But the Manchester United-red attire of Arthur soon pressed ahead again. From the other corner, the opponent - in rival City blue - was marked up quickly, noticeable damage forming under his face as the pair landed punishing blows.
Rea, 27, landed power punches but Arthur, 34, matched the intensity with effective uppercuts as the action seldom decreased over 12 rounds.
The victor edged the result with judges scorecards of even score, 115-113 and 115-112, but the two athletes were relentless and full of heart, everything their inspiration Hatton embodied.
