British light-heavyweight Buatsi made a winning yet unimpressive debut to his career under new promoters with a decision win over Zach Parker in Manchester.
The Olympic medal winner's punch output likely gained him a split decision in a competitive 10-round bout at the boxing arena.
But the challenger landed significant shots, connecting with powerful single shots in a contest where the styles never quite clicked, with constant grabbing marring the action.
The scoring judges had it 96-94 for to Buatsi, with the third a 95-95.
"It wasn't my finest performance but what do champions do? They win," the victor said in the ring as he was greeted with negative reactions from the audience.
The British fighter bounced back after his maiden career setback - an thrilling contest with his previous opponent in last winter - to secure a 20th pro success.
Various analysts felt the challenger, thirty-one, should have been awarded the decision but the Derbyshire fighter suffered the second loss of his 28-bout career.
Buatsi Claims Victory in Uneventful Encounter
Buatsi's progress has plateaued in recent years through contract problems and long spells of inactivity.
Once tipped as the next star of the British fight scene, he now stands trying to fulfil that early promise - possibly in what feels like a final roll of the dice - under fresh management.
He began cautiously, with the two boxers willing to take risks in a tentative opening few rounds.
The challenger, whose sole prior loss came at super-middleweight against his former opponent in two years ago after breaking his hand mid-fight, was competing in only his second bout at light-heavyweight.
By the halfway stage, the underdog had stayed in contention, causing problems for Buatsi, who operated with a tight guard to narrowly win the cleaner stanzas.
The spectators' acceptance decreased because of constant clinching, with Parker going down multiple occasions during clinches.
Parker closed well, but several stanzas were challenging to assess. Nevertheless, ex-champion Carl Frampton - providing analysis for Dazn - had it particularly wide for the challenger, scoring for Buatsi just a single round.
Buatsi advances, but with the presence of heavy hitter Benavidez, and Russian star Bivol dominating the weight class, the journey to titles - judging by this showing - still seems difficult.
Ricky Hatton Memorial Fuels Local Rivalry Contest
In the co-main event, Arthur defeated Rea by close verdict in a excellent all-Manchester battle to win the European light heavyweight title.
The arena fell silent for a deeply poignant homage before the fight as 10 bells sounded in honor of the city's native Hatton, who passed away aged 46 in recently.
It was the premier televised boxing event in the city since the passing of Hatton. As the final chime faded, the stillness became a shout of "there's just one Hatton".
The competition within the ring reflected the feeling. The eventual winner was sent to the canvas by a significant blow flush on the chin in the initial stage, rising shakily to his feet on the referee's count.
But the traditional red equipment of the fighter soon pressed ahead again. From the other corner, the opponent - in rival City blue - was injured soon, significant bruising developing under his orbital area as the fighters traded hard punches.
The challenger, 27, delivered effective strikes but Arthur, thirty-four, fought fire with fire with powerful upward punches as the intensity hardly diminished over 12 rounds.
Arthur barely secured the result with official scores of draw, close margin and clearer margin, but each competitor were determined and full of heart, exactly what their hero the legend represented.
