UK light-heavyweight Buatsi made a winning yet disappointing beginning to life under recent management with a decision win over Zach Parker in the Manchester arena.
The Olympic medal winner's activity level seemingly secured him a split decision in a close ten-round contest at the boxing arena.
But the challenger had his moments, delivering effective individual punches in a fight where the approaches never quite clicked, with frequent clinching spoiling the contest.
Two judges had it 96-94 to Buatsi, with the third a 95-95 draw.
"It wasn't my finest display but what defines champions? They win," Buatsi commented in the ring as he was greeted with boos from the crowd.
The Londoner bounced back after his first professional defeat - an memorable fight with his previous opponent in last winter - to claim a 20th career victory.
Several boxing experts felt the challenger, thirty-one, merited the decision but the British boxer experienced the second loss of his 28-fight career.
Buatsi Secures Triumph in Uneventful Encounter
Buatsi's progress has plateaued in recent years through promotional disputes and long spells of inactivity.
Earlier forecast as the future of UK boxing, he now is positioned trying to fulfil that early promise - maybe in what seems like a last chance - under recent support.
He started carefully, with neither fighter prepared to take risks in a cagey initial rounds.
Parker, whose only previous defeat came at super-middleweight against John Ryder in two years ago after breaking his hand mid-fight, was making just his second bout at light heavyweight.
By the halfway stage, Parker had kept it close, creating difficulties for the favorite, who utilized a protective stance to barely take the better stanzas.
The crowd's patience wore thin amid constant clinching, with the challenger going down several times during clinches.
Parker finished the stronger, but several stanzas were difficult to score. However, ex-champion Carl Frampton - providing analysis for the broadcast network - had it strongly leaning for the challenger, giving Buatsi just a single round.
The victor advances, but with the caliber of hard hitter David Benavidez, and Russian champion Dmitry Bivol leading the category, the path to championship success - judging by this showing - still seems difficult.
Ricky Hatton Homage Motivates Local Rivalry Contest
In the secondary fight, Arthur defeated Rea by close verdict in a terrific all-Manchester battle to win the European light-heavyweight championship.
The venue grew hushed for a extremely emotional memorial ahead of the contest as ten bells tolled in honor of the city's native Hatton, who succumbed aged 46 in last month.
It was the first major televised match card in the city since the passing of Hatton. As the final chime disappeared, the quiet transitioned to a shout of "only one Ricky Hatton".
The fighting inside the ropes reflected the sentiment. The eventual winner was sent to the canvas by a powerful punch directly to the jaw in the early round, rising shakily to his position on the eight count.
But the traditional red attire of Arthur soon advanced again. On the opposite side, Rea - in opposing blue - was damaged early, noticeable damage forming under his eye as the fighters landed punishing blows.
The challenger, twenty-seven, landed power punches but Arthur, thirty-four, responded in kind with powerful upward punches as the action rarely dropped over the full distance.
The victor barely secured the decision with scoring tallies of 114-114, close margin and wider gap, but both fighters were determined and courageous, everything their idol the legend embodied.
