British light-heavyweight Buatsi secured a victory yet underwhelming debut to his career under fresh promotional backing with a decision win over Zach Parker in Manchester.
The Olympic medal winner's work rate seemingly secured him a judges' verdict in a close 10-round contest at the Manchester venue.
But the challenger landed significant shots, landing some telling clean blows in a contest where the approaches didn't complement each other, with frequent clinching disrupting the action.
The scoring judges had it 96-94 for to Buatsi, with the remaining official a even score.
"It wasn't my finest showing but what do champions do? They succeed," the victor stated in the ring as he was faced boos from the spectators.
The Londoner bounced back after his initial pro loss - an thrilling contest with his previous opponent in February - to secure a 20th career victory.
Some ringside observers felt Parker, 31, should have been awarded the victory but the Derbyshire fighter suffered the second defeat of his 28-bout professional journey.
The Champion Secures Triumph in Slow Encounter
His career development has plateaued in the past few years through management issues and long spells of inactivity.
Previously predicted as the future of the British fight scene, he now finds himself trying to realize his potential - maybe in what appears to be a last chance - under fresh management.
He started carefully, with the two boxers prepared to be aggressive in a cagey initial rounds.
The challenger, whose only previous defeat came at super-middleweight against John Ryder in two years ago after breaking his hand in the contest, was making just his second bout at the higher weight class.
By the fight's midpoint, the underdog had made it competitive, making life awkward for Buatsi, who operated with a tight guard to edge the more effective periods.
The crowd's patience decreased amid frequent holding, with Parker slipping to the canvas several times during close exchanges.
Parker closed well, but many rounds were difficult to score. Although, previous titleholder the boxing analyst - providing analysis for the broadcast network - had it strongly leaning for the challenger, scoring for Buatsi just one round.
Buatsi advances, but with the caliber of hard hitter David Benavidez, and Eastern European fighter Bivol dominating the weight class, the path to championship success - on this evidence - still looks steep.
Ricky Hatton Memorial Inspires Local Rivalry Fight
In the supporting bout, Arthur overcame Rea by close verdict in a outstanding Manchester vs Manchester fight to secure the European light-heavyweight championship.
The stadium fell silent for a profoundly moving tribute before the fight as a bell ceremony tolled in memory of Manchester's own Hatton, who died 46 years old in September.
It was the premier televised boxing event in the urban center since Hatton's death. As the concluding sound faded, the quiet became a roar of "there's only one Ricky Hatton".
The fighting inside the ropes reflected the emotion. Arthur was sent to the canvas by a significant blow squarely on the chin in the early round, standing uncertainly to his footing on the eight count.
But the red-colored equipment of Arthur soon pressed ahead again. From the other corner, Rea - in rival City blue - was damaged soon, noticeable damage appearing under his eye as the pair exchanged hard punches.
Rea, twenty-seven, landed power punches but Arthur, 34, matched the intensity with powerful upward punches as the action seldom decreased over 12 rounds.
The victor barely secured the decision with official scores of 114-114, 115-113 and 115-112, but the two athletes were persistent and full of heart, exactly what their hero the legend represented.
