UK light-heavyweight Buatsi earned a win yet unimpressive start to his career under recent management with a decision win over Zach Parker in Manchester.
The Olympic medal winner's punch output appeared to earn him a split decision in a tight ten-round bout at the Manchester venue.
But Parker landed significant shots, landing some telling clean blows in a fight where the approaches didn't complement each other, with constant grabbing spoiling the fight.
The scoring judges had it 96-94 for to Buatsi, with the remaining official a 95-95 draw.
"It wasn't my greatest display but what defines champions? They prevail," Buatsi commented in the ringside as he was met by negative reactions from the crowd.
The Londoner got back to winning after his maiden career setback - an epic battle with Callum Smith in last winter - to earn a 20th career victory.
Some ringside observers thought Parker, thirty-one, deserved the decision but the British boxer experienced the second loss of his 28-fight professional journey.
Buatsi Secures Triumph in Dull Affair
Buatsi's progress has stalled in recent years through contract problems and considerable time of inactivity.
Earlier forecast as the rising talent of the British fight scene, he now finds himself trying to fulfil that early promise - perhaps in what feels like a ultimate opportunity - under fresh management.
He began cautiously, with neither fighter prepared to take risks in a cagey opening few rounds.
Parker, whose only previous defeat came at super middleweight against his former opponent in two years ago after damaging his hand in the contest, was making just his second bout at light heavyweight.
By the halfway stage, the underdog had stayed in contention, creating difficulties for Buatsi, who worked behind a tight guard to barely take the better rounds.
The spectators' acceptance diminished because of frequent holding, with the challenger falling to the floor various instances during clinches.
Parker finished the stronger, but multiple periods were difficult to score. Nevertheless, former world champion Carl Frampton - providing analysis for the broadcast network - had it significantly in favor for Parker, giving Buatsi just a single round.
Buatsi moves on, but with the likes of heavy hitter David Benavidez, and Russian champion Bivol ruling the division, the path to championship success - based on this performance - still appears challenging.
Hatton Homage Inspires All-Manchester Fight
In the co-main event, Arthur defeated Bradley Rea by split-decision in a outstanding Manchester vs Manchester fight to win the European light heavyweight championship.
The venue fell silent for a extremely emotional tribute prior to the bout as 10 bells sounded in memory of the city's native Ricky Hatton, who succumbed 46 years old in last month.
It was the initial significant broadcast fight night in the urban center since the passing of Hatton. As the final chime disappeared, the silence became a roar of "there's only one Ricky Hatton".
The action inside the ropes reflected the emotion. The eventual winner was floored by a significant blow directly to the chin in the initial stage, standing uncertainly to his feet on the eight count.
But the Manchester United-red equipment of Arthur soon pressed ahead again. Across the ring, Rea - in competitive blue - was injured soon, significant bruising appearing under his orbital area as the fighters landed powerful shots.
Rea, twenty-seven, delivered effective strikes but Arthur, thirty-four, responded in kind with stinging uppercuts as the pace seldom decreased over the full distance.
Arthur narrowly won the result with scoring tallies of draw, narrow lead and wider gap, but each competitor were persistent and full of heart, all the qualities their inspiration the legend embodied.
