British light-heavyweight Buatsi made a winning yet unimpressive debut to his career under fresh promotional backing with a points victory over Zach Parker in the Manchester arena.
The Olympic medal winner's punch output appeared to earn him a majority decision in a competitive ten-round bout at the Manchester venue.
But Parker found success, delivering effective clean blows in a fight where the styles didn't complement each other, with constant grabbing marring the fight.
The officials judged it 96-94 to Buatsi, with the remaining official a even score.
"It wasn't my best display but how do champions respond? They prevail," the victor stated in the ring as he was met by disapproval from the spectators.
The Londoner returned to winning ways after his first professional defeat - an memorable fight with Callum Smith in February - to earn a twentieth professional win.
Several boxing experts thought the challenger, 31, should have been awarded the win but the contender experienced the second loss of his 28-fight career.
Buatsi Secures Victory in Dull Encounter
His career development has slowed in recent times through management issues and considerable time of inactivity.
Earlier forecast as the next star of British boxing, he now is positioned trying to fulfil that early promise - possibly in what seems like a final roll of the dice - under fresh management.
He started carefully, with the two boxers prepared to be aggressive in a tentative initial rounds.
Parker, whose sole prior loss came at super-middleweight against his former opponent in 2022 after damaging his hand mid-fight, was participating in his second bout at the higher weight class.
By the middle rounds, the underdog had kept it close, creating difficulties for the favorite, who worked behind a protective stance to edge the cleaner periods.
The audience's tolerance diminished amid constant clinching, with Parker slipping to the canvas multiple occasions during grappling.
Parker closed well, but multiple periods were challenging to assess. Although, former world champion the boxing analyst - commentating on the broadcast network - had it strongly leaning for the challenger, giving Buatsi just one round.
Buatsi progresses, but with the presence of heavy hitter Benavidez, and Russian star Dmitry Bivol leading the category, the road to world glory - judging by this showing - still looks steep.
Ricky Hatton Tribute Inspires Manchester Derby Fight
In the co-main event, Arthur overcame Rea by split-decision in a excellent local rivalry fight to win the continental championship.
The stadium grew hushed for a extremely emotional tribute before the fight as ten bells sounded in memory of the city's native Ricky Hatton, who died 46 years old in September.
It was the initial significant broadcast match card in the city since Hatton's passing. As the concluding sound disappeared, the stillness transitioned to a chant of "only one Ricky Hatton".
The action within the ring reflected the sentiment. The eventual winner was sent to the canvas by a significant blow flush on the face in the second round, rising shakily to his footing on the eight count.
But the traditional red equipment of Arthur soon advanced again. From the other corner, Rea - in competitive blue - was injured soon, significant bruising forming under his face as the pair traded powerful shots.
Rea, twenty-seven, connected with strong blows but Arthur, thirty-four, matched the intensity with effective uppercuts as the intensity rarely dropped over 12 rounds.
Arthur barely secured the verdict with judges scorecards of draw, narrow lead and 115-112, but both fighters were relentless and full of heart, all the qualities their idol the legend stood for.
