British light heavyweight Buatsi earned a win yet disappointing debut to life under recent management with a decision win over Zach Parker in the Manchester arena.
The Olympic bronze medallist's activity level likely gained him a majority decision in a competitive ten-round contest at the Co-op Live Arena.
But the challenger had his moments, landing some telling clean blows in a fight where the styles never quite clicked, with excessive holding spoiling the action.
The scoring judges judged it 96-94 to Buatsi, with the final judge a 95-95.
"It wasn't my finest display but what do champions do? They win," Buatsi commented in the ringside as he was faced negative reactions from the crowd.
The Londoner returned to winning ways after his first professional defeat - an memorable fight with his previous opponent in last winter - to claim a 20th pro success.
Several boxing experts thought Parker, thirty-one, deserved the victory but the Derbyshire fighter experienced the second setback of his 28-bout professional journey.
The Champion Secures Victory in Dull Match
His career development has stalled in recent times through management issues and considerable time of lack of fights.
Once tipped as the future of UK boxing, he now stands trying to realize his potential - perhaps in what seems like a ultimate opportunity - under recent support.
He began cautiously, with both competitors willing to overcommit in a tentative initial rounds.
The challenger, whose sole prior loss came at super-middleweight against his former opponent in two years ago after suffering a hand injury during the bout, was participating in his second appearance at the higher weight class.
By the halfway stage, Parker had kept it close, creating difficulties for Buatsi, who worked behind a tight guard to barely take the cleaner rounds.
The audience's tolerance decreased during regular grabbing, with the challenger going down multiple occasions during close exchanges.
Parker ended stronger, but many rounds were hard to judge. Nevertheless, ex-champion the boxing analyst - working with Dazn - had it strongly leaning for Parker, scoring for Buatsi just a single round.
The victor moves on, but with the presence of hard hitter Benavidez, and Eastern European fighter Bivol ruling the division, the path to championship success - on this evidence - still looks steep.
Ricky Hatton Memorial Fuels Manchester Derby Battle
In the co-main event, Lyndon Arthur defeated Bradley Rea by close verdict in a terrific all-Manchester contest to win the European light-heavyweight championship.
The arena grew hushed for a deeply poignant homage prior to the bout as a bell ceremony sounded in honor of the city's native Hatton, who succumbed aged 46 in last month.
It was the premier televised match card in the urban center since the passing of Hatton. As the last bell ended, the silence transitioned to a chant of "there's just one Ricky Hatton".
The fighting during the bout reflected the sentiment. Arthur was sent to the canvas by a significant blow flush on the face in the second round, getting up unsteadily to his footing on the referee's count.
But the traditional red shorts of Arthur soon advanced again. From the other corner, Rea - in competitive blue - was damaged soon, significant bruising appearing under his eye as the duo landed punishing blows.
The challenger, twenty-seven, landed power punches but the champion, thirty-four, responded in kind with stinging uppercuts as the intensity hardly diminished over 12 rounds.
Arthur barely secured the result with official scores of even score, close margin and clearer margin, but each competitor were persistent and courageous, exactly what their idol the legend embodied.
