British light-heavyweight Buatsi earned a win yet unimpressive beginning to life under recent management with a unanimous decision over Zach Parker in Manchester.
The Olympic medal winner's activity level appeared to earn him a majority decision in a competitive ten-round contest at the Manchester venue.
But Parker landed significant shots, delivering effective clean blows in a contest where the techniques never quite clicked, with excessive holding disrupting the fight.
The officials judged it 96-94 for to Buatsi, with the third a 95-95.
"It wasn't my best showing but how do champions respond? They win," Buatsi said in the arena as he was met by disapproval from the audience.
The British fighter got back to winning after his maiden career setback - an epic battle with his previous opponent in February - to claim a 20th pro success.
Some ringside observers believed the challenger, 31, deserved the victory but the Derbyshire fighter endured the second loss of his 28-fight professional journey.
Buatsi Earns Win in Uneventful Affair
The fighter's advancement has plateaued in recent times through contract problems and long spells of lack of fights.
Earlier forecast as the next star of UK boxing, he now stands trying to realize his potential - maybe in what feels like a final roll of the dice - under recent support.
He started carefully, with both competitors ready to overcommit in a tentative early stages.
Parker, whose sole prior loss came at super middleweight against his former opponent in two years ago after damaging his hand in the contest, was competing in only his second appearance at light heavyweight.
By the fight's midpoint, the underdog had stayed in contention, creating difficulties for Buatsi, who operated with a protective stance to edge the cleaner stanzas.
The crowd's patience decreased amid frequent holding, with the challenger slipping to the canvas multiple occasions during clinches.
Parker ended stronger, but multiple periods were hard to judge. Nevertheless, previous titleholder the boxing analyst - commentating on Dazn - had it particularly wide for the challenger, scoring for Buatsi just one round.
The victor progresses, but with the presence of power puncher Benavidez, and Russian star Bivol dominating the weight class, the road to world glory - based on this performance - still looks steep.
Hatton Memorial Fuels Local Rivalry Fight
In the co-main event, Arthur beat Bradley Rea by split-decision in a outstanding Manchester vs Manchester contest to capture the European light-heavyweight belt.
The venue grew hushed for a extremely emotional tribute before the fight as ten bells tolled in memory of local hero Ricky Hatton, who succumbed at age 46 in last month.
It was the first major televised match card in the city since Hatton's passing. As the concluding sound disappeared, the quiet became a shout of "there's just one Ricky Hatton".
The action during the bout reflected the emotion. The eventual winner was sent to the canvas by a left hook flush on the jaw in the early round, getting up unsteadily to his position on the referee's count.
But the Manchester United-red equipment of the fighter soon advanced again. On the opposite side, the opponent - in rival City blue - was marked up soon, noticeable damage forming under his eye as the pair landed hard punches.
The challenger, twenty-seven, landed power punches but Arthur, thirty-four, fought fire with fire with stinging uppercuts as the pace seldom decreased over the full distance.
The victor barely secured the result with judges scorecards of 114-114, 115-113 and clearer margin, but the two athletes were relentless and full of heart, all the qualities their hero the legend represented.
