British light-heavyweight Buatsi secured a victory yet underwhelming debut to life under new promoters with a unanimous decision over Zach Parker in the Manchester arena.
The Olympic bronze medallist's punch output seemingly secured him a split decision in a competitive ten-round fight at the boxing arena.
But the challenger had his moments, delivering effective single shots in a contest where the techniques didn't complement each other, with excessive holding marring the action.
Two judges had it 96-94 to the winner, with the remaining official a 95-95 draw.
"It wasn't my greatest showing but what defines champions? They win," Buatsi stated in the ring as he was met by negative reactions from the audience.
The Londoner returned to winning ways after his maiden career setback - an thrilling contest with Callum Smith in February - to claim a 20th pro success.
Various analysts felt Parker, thirty-one, deserved the decision but the Derbyshire fighter experienced the second defeat of his 28-bout career.
The Champion Earns Win in Dull Encounter
The fighter's advancement has plateaued in recent times through contract problems and extended periods of inactivity.
Once tipped as the next star of British boxing, he now is positioned trying to fulfil that early promise - possibly in what seems like a ultimate opportunity - under fresh management.
He opened tentatively, with both competitors prepared to be aggressive in a calculated opening few rounds.
Parker, whose single earlier setback came at super middleweight against John Ryder in 2022 after suffering a hand injury mid-fight, was making just his second fight at light heavyweight.
By the fight's midpoint, the underdog had kept it close, causing problems for the favorite, who utilized a protective stance to barely take the better periods.
The audience's tolerance diminished amid frequent holding, with the challenger falling to the floor several times during grappling.
The underdog finished the stronger, but many rounds were difficult to score. Nevertheless, ex-champion Carl Frampton - providing analysis for the broadcast network - had it particularly wide for Parker, giving Buatsi just only one stanza.
Buatsi moves on, but with the likes of heavy hitter David Benavidez, and Russian champion Dmitry Bivol leading the category, the path to championship success - on this evidence - still looks steep.
Hatton Memorial Motivates All-Manchester Battle
In the supporting bout, Lyndon Arthur defeated Rea by split-decision in a outstanding local rivalry battle to capture the continental championship.
The venue fell silent for a extremely emotional homage before the fight as ten bells rang in honor of the city's native Hatton, who succumbed 46 years old in recently.
It was the premier televised boxing event in the location since Hatton's passing. As the final chime disappeared, the quiet transitioned to a shout of "there's only one Hatton".
The action during the bout matched the sentiment. The eventual winner was sent to the canvas by a powerful punch flush on the jaw in the initial stage, rising shakily to his feet on the count of eight.
But the red-colored attire of the fighter soon pressed ahead again. On the opposite side, Rea - in competitive blue - was damaged soon, noticeable damage forming under his eye as the pair exchanged punishing blows.
The challenger, twenty-seven, delivered effective strikes but Arthur, thirty-four, responded in kind with powerful upward punches as the pace rarely dropped over 12 rounds.
Arthur edged the decision with scoring tallies of 114-114, narrow lead and clearer margin, but both fighters were persistent and full of heart, everything their idol the legend stood for.
