UK light heavyweight Buatsi made a winning yet unimpressive beginning to life under recent management with a decision win over Zach Parker in Manchester.
The Olympic medal winner's activity level seemingly secured him a judges' verdict in a close 10-round contest at the Co-op Live Arena.
But the challenger had his moments, landing some telling individual punches in a contest where the techniques never quite clicked, with frequent clinching disrupting the contest.
The scoring judges scored it 96-94 for to Buatsi, with the final judge a 95-95 draw.
"It wasn't my greatest display but what do champions do? They win," the victor commented in the ring as he was greeted with boos from the audience.
The Londoner returned to winning ways after his initial pro loss - an thrilling contest with Callum Smith in February - to secure a 20th pro success.
Some ringside observers thought Parker, thirty-one, merited the decision but the contender experienced the second defeat of his 28-bout career.
The Champion Claims Victory in Dull Match
The fighter's advancement has stalled in recent years through promotional disputes and long spells of inactivity.
Once tipped as the future of British boxing, he now stands trying to fulfil that early promise - maybe in what feels like a ultimate opportunity - under recent support.
He opened tentatively, with the two boxers willing to take risks in a tentative opening few rounds.
Parker, whose only previous defeat came at super middleweight against John Ryder in two years ago after suffering a hand injury in the contest, was competing in only his second bout at light-heavyweight.
By the middle rounds, the underdog had made it competitive, causing problems for Buatsi, who utilized a solid defense to barely take the cleaner periods.
The spectators' acceptance diminished during constant clinching, with the challenger going down several times during clinches.
The underdog finished the stronger, but many rounds were hard to judge. Nevertheless, ex-champion the boxing analyst - commentating on the broadcast network - had it significantly in favor for the challenger, awarding Buatsi just one round.
Buatsi progresses, but with the likes of power puncher Benavidez, and Russian star Dmitry Bivol dominating the weight class, the road to world glory - judging by this showing - still seems difficult.
Hatton Homage Fuels Manchester Derby Contest
In the co-main event, Arthur beat Rea by close verdict in a terrific Manchester vs Manchester battle to capture the European light heavyweight championship.
The arena became quiet for a deeply poignant homage ahead of the contest as ten bells tolled in memory of the city's native Ricky Hatton, who died 46 years old in September.
It was the first major televised match card in the urban center since the passing of Hatton. As the last bell faded, the silence transitioned to a chant of "there's only one Ricky Hatton".
The fighting inside the ropes matched the emotion. The eventual winner was knocked down by a powerful punch squarely on the jaw in the initial stage, rising shakily to his position on the eight count.
But the Manchester United-red attire of the fighter soon advanced again. From the other corner, the opponent - in opposing blue - was marked up soon, heavy swelling developing under his eye as the pair landed hard punches.
The challenger, 27, delivered effective strikes but the champion, thirty-four, matched the intensity with powerful upward punches as the pace rarely dropped over the full distance.
The victor narrowly won the verdict with judges scorecards of 114-114, narrow lead and clearer margin, but each competitor were relentless and full of heart, everything their hero the legend represented.
