UK light heavyweight Buatsi made a winning yet disappointing beginning to his career under recent management with a decision win over Zach Parker in the Manchester arena.
The Olympic medal winner's punch output seemingly secured him a majority decision in a tight 10-round fight at the boxing arena.
But the challenger had his moments, connecting with powerful single shots in a fight where the techniques didn't complement each other, with excessive holding disrupting the contest.
The scoring judges judged it 96-94 to Buatsi, with the final judge a even score.
"It wasn't my greatest showing but how do champions respond? They succeed," the victor commented in the ring as he was greeted with negative reactions from the crowd.
The Londoner bounced back after his maiden career setback - an memorable fight with his previous opponent in February - to secure a twentieth professional win.
Various analysts believed the challenger, 31, deserved the victory but the British boxer experienced the second loss of his 28-bout professional journey.
The Champion Earns Win in Slow Match
The fighter's advancement has slowed in recent years through contract problems and extended periods of lack of fights.
Previously predicted as the rising talent of the British fight scene, he now is positioned trying to realize his potential - perhaps in what seems like a final roll of the dice - under new promotional backing.
He started carefully, with both competitors prepared to take risks in a tentative opening few rounds.
Parker, whose sole prior loss came at the lower weight class against John Ryder in two years ago after damaging his hand in the contest, was making just his second appearance at the higher weight class.
By the middle rounds, the underdog had stayed in contention, causing problems for the favorite, who operated with a protective stance to narrowly win the better rounds.
The audience's tolerance wore thin because of frequent holding, with the challenger going down several times during close exchanges.
The underdog finished the stronger, but several stanzas were challenging to assess. Although, previous titleholder Carl Frampton - commentating on the broadcast network - had it particularly wide for Parker, scoring for Buatsi just one round.
Buatsi advances, but with the presence of heavy hitter David Benavidez, and Russian star Dmitry Bivol dominating the weight class, the road to world glory - on this evidence - still looks steep.
Hatton Memorial Motivates Local Rivalry Fight
In the co-main event, Arthur defeated Bradley Rea by close verdict in a outstanding local rivalry battle to win the continental championship.
The stadium became quiet for a extremely emotional homage prior to the bout as a bell ceremony tolled in memory of the city's native Hatton, who succumbed aged 46 in September.
It was the first major televised boxing event in the location since Hatton's passing. As the final chime ended, the stillness became a shout of "there's just one Hatton".
The competition inside the ropes reflected the feeling. Arthur was knocked down by a left hook directly to the jaw in the early round, standing uncertainly to his position on the eight count.
But the red-colored shorts of Arthur soon pressed ahead again. On the opposite side, the opponent - in opposing blue - was damaged quickly, heavy swelling forming under his face as the fighters landed powerful shots.
The challenger, twenty-seven, delivered effective strikes but Arthur, thirty-four, matched the intensity with powerful upward punches as the action rarely dropped over twelve rounds.
Arthur narrowly won the result with scoring tallies of 114-114, close margin and 115-112, but both fighters were persistent and courageous, all the qualities their idol the legend embodied.
