UK light heavyweight Buatsi made a winning yet disappointing debut to life under recent management with a decision win over Zach Parker in Manchester.
The Olympic medal winner's work rate appeared to earn him a majority decision in a close ten-round bout at the Co-op Live Arena.
But the challenger landed significant shots, connecting with powerful individual punches in a match where the styles never quite clicked, with constant grabbing marring the action.
The scoring judges had it 96-94 for to Buatsi, with the remaining official a 95-95 draw.
"It wasn't my best performance but how do champions respond? They win," Buatsi commented in the ringside as he was faced negative reactions from the audience.
The Londoner got back to winning after his first professional defeat - an memorable fight with his previous opponent in February - to secure a twentieth professional win.
Various analysts felt Parker, 31, deserved the win but the British boxer endured the second setback of his 28-bout professional journey.
Buatsi Claims Win in Slow Encounter
Buatsi's progress has plateaued in the past few years through contract problems and considerable time of lack of fights.
Earlier forecast as the next star of UK boxing, he now stands trying to achieve expectations - maybe in what seems like a ultimate opportunity - under fresh management.
He began cautiously, with neither fighter ready to take risks in a tentative opening few rounds.
Parker, whose only previous defeat came at super-middleweight against his former opponent in two years ago after breaking his hand in the contest, was participating in his second appearance at light-heavyweight.
By the halfway stage, the underdog had kept it close, causing problems for Buatsi, who utilized a tight guard to narrowly win the cleaner rounds.
The audience's tolerance wore thin because of constant clinching, with the challenger going down several times during clinches.
Parker closed well, but many rounds were hard to judge. Nevertheless, former world champion the boxing analyst - providing analysis for the broadcast network - had it significantly in favor for the challenger, awarding Buatsi just a single round.
Buatsi advances, but with the presence of hard hitter David Benavidez, and Russian star Dmitry Bivol leading the category, the journey to titles - on this evidence - still seems difficult.
Ricky Hatton Tribute Motivates Local Rivalry Fight
In the supporting bout, Lyndon Arthur beat Bradley Rea by split-decision in a outstanding local rivalry battle to secure the European light heavyweight belt.
The arena became quiet for a deeply poignant tribute prior to the bout as 10 bells sounded in remembrance of Manchester's own Hatton, who passed away at age 46 in September.
It was the premier televised boxing event in the city since Hatton's death. As the concluding sound disappeared, the silence became a shout of "only one Hatton".
The fighting within the ring equaled the feeling. The eventual winner was floored by a left hook directly to the chin in the second round, rising shakily to his feet on the referee's count.
But the traditional red attire of the fighter soon came forward again. On the opposite side, the opponent - in competitive blue - was damaged soon, significant bruising developing under his face as the fighters exchanged punishing blows.
Rea, twenty-seven, delivered effective strikes but the champion, 34, responded in kind with powerful upward punches as the pace rarely dropped over 12 rounds.
The victor barely secured the result with official scores of draw, 115-113 and 115-112, but the two athletes were persistent and courageous, all the qualities their inspiration the legend embodied.
