UK light-heavyweight Buatsi earned a win yet unimpressive beginning to life under recent management with a unanimous decision over Zach Parker in the Manchester arena.
The Olympic bronze medallist's work rate appeared to earn him a majority decision in a competitive ten-round contest at the Manchester venue.
But the challenger had his moments, landing some telling clean blows in a fight where the approaches didn't complement each other, with excessive holding disrupting the contest.
The scoring judges judged it 96-94 in favor to Buatsi, with the third a 95-95.
"It wasn't my best showing but what do champions do? They succeed," the victor said in the arena as he was greeted with negative reactions from the spectators.
The British fighter bounced back after his first professional defeat - an epic battle with Callum Smith in last winter - to secure a twentieth professional win.
Various analysts believed the challenger, thirty-one, deserved the win but the British boxer experienced the second loss of his 28-match career.
Buatsi Secures Win in Slow Match
Buatsi's progress has stalled in the past few years through contract problems and long spells of inactivity.
Previously predicted as the next star of UK boxing, he now stands trying to achieve expectations - maybe in what feels like a last chance - under fresh management.
He opened tentatively, with neither fighter willing to be aggressive in a cagey opening few rounds.
Parker, whose sole prior loss came at the lower weight class against his former opponent in 2022 after suffering a hand injury mid-fight, was competing in only his second fight at light heavyweight.
By the middle rounds, Parker had stayed in contention, making life awkward for Buatsi, who operated with a protective stance to edge the better rounds.
The audience's tolerance decreased amid frequent holding, with Parker falling to the floor several times during clinches.
Parker finished the stronger, but several stanzas were hard to judge. However, ex-champion Carl Frampton - commentating on Dazn - had it strongly leaning for the challenger, scoring for Buatsi just only one stanza.
The victor progresses, but with the likes of hard hitter David Benavidez, and Russian champion Bivol leading the category, the journey to titles - based on this performance - still seems difficult.
Hatton Memorial Inspires Manchester Derby Battle
In the supporting bout, Lyndon Arthur beat Bradley Rea by split-decision in a outstanding local rivalry fight to win the European light heavyweight belt.
The venue grew hushed for a deeply poignant memorial ahead of the contest as ten bells sounded in remembrance of Manchester's own Ricky Hatton, who died 46 years old in September.
It was the premier televised boxing event in the city since Hatton's passing. As the concluding sound ended, the silence became a chant of "there's just one Ricky Hatton".
The competition during the bout equaled the feeling. The eventual winner was knocked down by a powerful punch squarely on the jaw in the initial stage, getting up unsteadily to his position on the eight count.
But the traditional red equipment of Arthur soon advanced again. Across the ring, the opponent - in rival City blue - was marked up quickly, noticeable damage appearing under his orbital area as the fighters exchanged punishing blows.
The challenger, twenty-seven, connected with strong blows but the champion, thirty-four, fought fire with fire with stinging uppercuts as the intensity seldom decreased over twelve rounds.
The victor barely secured the verdict with official scores of even score, close margin and 115-112, but both fighters were persistent and courageous, exactly what their hero Hatton represented.
