UK light heavyweight Buatsi earned a win yet disappointing beginning to his career under recent management with a points victory over Zach Parker in the Manchester arena.
The Olympic bronze medallist's activity level seemingly secured him a split decision in a close ten-round bout at the Manchester venue.
But the challenger landed significant shots, delivering effective individual punches in a match where the approaches didn't complement each other, with excessive holding marring the fight.
The officials had it 96-94 to Buatsi, with the third a even score.
"It wasn't my greatest display but what defines champions? They prevail," Buatsi commented in the arena as he was faced negative reactions from the crowd.
The British fighter got back to winning after his initial pro loss - an thrilling contest with his previous opponent in last winter - to earn a 20th career victory.
Several boxing experts thought Parker, 31, merited the victory but the contender suffered the second defeat of his 28-match career.
Buatsi Claims Win in Slow Encounter
The fighter's advancement has plateaued in recent times through promotional disputes and considerable time of inactivity.
Previously predicted as the future of UK boxing, he now stands trying to realize his potential - possibly in what seems like a ultimate opportunity - under recent support.
He started carefully, with both competitors ready to be aggressive in a calculated opening few rounds.
The challenger, whose only previous defeat came at super middleweight against John Ryder in 2022 after suffering a hand injury in the contest, was making just his second fight at light heavyweight.
By the middle rounds, Parker had made it competitive, making life awkward for the favorite, who utilized a protective stance to narrowly win the better periods.
The audience's tolerance decreased because of constant clinching, with Parker falling to the floor several times during clinches.
Parker closed well, but multiple periods were hard to judge. However, previous titleholder Carl Frampton - commentating on Dazn - had it strongly leaning for Parker, scoring for Buatsi just a single round.
Buatsi progresses, but with the likes of heavy hitter David Benavidez, and Russian champion Bivol dominating the weight class, the journey to titles - judging by this showing - still seems difficult.
Hatton Tribute Motivates Manchester Derby Fight
In the secondary fight, Lyndon Arthur defeated Bradley Rea by split-decision in a excellent local rivalry battle to win the European light-heavyweight title.
The venue became quiet for a profoundly moving homage ahead of the contest as 10 bells rang in remembrance of the city's native Ricky Hatton, who passed away 46 years old in last month.
It was the first major televised match card in the location since Hatton's passing. As the last bell faded, the stillness gave way to a shout of "only one Hatton".
The fighting inside the ropes reflected the emotion. The eventual winner was sent to the canvas by a significant blow flush on the jaw in the early round, getting up unsteadily to his position on the referee's count.
But the traditional red attire of Arthur soon pressed ahead again. Across the ring, Rea - in opposing blue - was injured early, heavy swelling developing under his orbital area as the fighters exchanged punishing blows.
Rea, twenty-seven, connected with strong blows but Arthur, thirty-four, fought fire with fire with effective uppercuts as the action rarely dropped over the full distance.
Arthur barely secured the decision with judges scorecards of even score, 115-113 and 115-112, but each competitor were persistent and full of heart, everything their idol the legend stood for.
