UK light-heavyweight Buatsi secured a victory yet underwhelming debut to his career under fresh promotional backing with a decision win over Zach Parker in the Manchester arena.
The Olympic bronze medallist's punch output seemingly secured him a majority decision in a tight 10-round contest at the boxing arena.
But the challenger had his moments, connecting with powerful individual punches in a fight where the techniques failed to mesh, with constant grabbing spoiling the action.
The officials judged it 96-94 to Buatsi, with the remaining official a 95-95.
"It wasn't my greatest showing but how do champions respond? They win," the victor said in the ringside as he was met by negative reactions from the spectators.
The British fighter bounced back after his initial pro loss - an epic battle with his previous opponent in last winter - to earn a twentieth professional win.
Various analysts thought the challenger, thirty-one, merited the win but the contender experienced the second setback of his 28-fight career.
Buatsi Secures Triumph in Uneventful Affair
Buatsi's progress has slowed in recent years through management issues and long spells of lack of fights.
Previously predicted as the rising talent of UK boxing, he now finds himself trying to achieve expectations - possibly in what feels like a last chance - under recent support.
He started carefully, with both competitors willing to take risks in a cagey opening few rounds.
Parker, whose single earlier setback came at super middleweight against his former opponent in two years ago after suffering a hand injury mid-fight, was participating in his second appearance at light heavyweight.
By the fight's midpoint, the underdog had stayed in contention, creating difficulties for Buatsi, who utilized a tight guard to barely take the cleaner stanzas.
The audience's tolerance diminished during regular grabbing, with the challenger falling to the floor multiple occasions during clinches.
Parker closed well, but several stanzas were challenging to assess. However, ex-champion Carl Frampton - commentating on the broadcast network - had it significantly in favor for the challenger, giving Buatsi just only one stanza.
Buatsi moves on, but with the presence of hard hitter Benavidez, and Russian champion Dmitry Bivol ruling the division, the path to championship success - based on this performance - still appears challenging.
Hatton Homage Fuels Local Rivalry Fight
In the co-main event, Arthur beat Rea by close verdict in a outstanding local rivalry contest to secure the continental belt.
The arena became quiet for a deeply poignant tribute before the fight as 10 bells sounded in memory of the city's native Hatton, who died at age 46 in September.
It was the premier televised match card in the location since Hatton's death. As the last bell ended, the silence transitioned to a roar of "only one Hatton".
The competition during the bout reflected the sentiment. Arthur was sent to the canvas by a powerful punch directly to the face in the early round, getting up unsteadily to his feet on the eight count.
But the Manchester United-red equipment of Arthur soon pressed ahead again. Across the ring, the opponent - in rival City blue - was marked up quickly, noticeable damage developing under his eye as the duo traded powerful shots.
The challenger, 27, landed power punches but Arthur, thirty-four, fought fire with fire with effective uppercuts as the action rarely dropped over the full distance.
Arthur edged the result with official scores of draw, close margin and clearer margin, but the two athletes were relentless and full of heart, exactly what their hero Hatton embodied.
