British light-heavyweight Buatsi secured a victory yet disappointing beginning to his career under recent management with a decision win over Zach Parker in the Manchester arena.
The Olympic bronze medallist's work rate appeared to earn him a split decision in a close 10-round contest at the Co-op Live Arena.
But Parker had his moments, connecting with powerful individual punches in a match where the approaches never quite clicked, with excessive holding spoiling the contest.
Two judges judged it 96-94 in favor to Buatsi, with the final judge a 95-95 draw.
"It wasn't my best showing but what defines champions? They succeed," Buatsi stated in the arena as he was met by boos from the audience.
The Londoner bounced back after his first professional defeat - an epic battle with Callum Smith in last winter - to claim a twentieth professional win.
Some ringside observers thought Parker, thirty-one, deserved the victory but the contender endured the second loss of his 28-fight career.
Buatsi Earns Triumph in Uneventful Match
The fighter's advancement has slowed in the past few years through promotional disputes and considerable time of inactivity.
Once tipped as the future of the British fight scene, he now is positioned trying to realize his potential - maybe in what appears to be a last chance - under recent support.
He began cautiously, with both competitors willing to overcommit in a calculated early stages.
Parker, whose only previous defeat came at the lower weight class against his former opponent in two years ago after suffering a hand injury mid-fight, was competing in only his second fight at the higher weight class.
By the fight's midpoint, Parker had stayed in contention, causing problems for Buatsi, who operated with a tight guard to barely take the better stanzas.
The crowd's patience decreased amid frequent holding, with the challenger falling to the floor various instances during close exchanges.
Parker finished the stronger, but many rounds were hard to judge. However, former world champion Carl Frampton - working with Dazn - had it significantly in favor for Parker, awarding Buatsi just only one stanza.
The victor moves on, but with the presence of power puncher David Benavidez, and Russian champion Bivol dominating the weight class, the road to world glory - based on this performance - still appears challenging.
Ricky Hatton Tribute Motivates Manchester Derby Fight
In the supporting bout, Arthur defeated Rea by divided decision in a outstanding Manchester vs Manchester contest to win the European light-heavyweight championship.
The arena became quiet for a deeply poignant memorial before the fight as a bell ceremony tolled in memory of the city's native Ricky Hatton, who passed away at age 46 in last month.
It was the premier televised boxing event in the location since Hatton's death. As the final chime disappeared, the quiet gave way to a chant of "there's just one Hatton".
The competition during the bout equaled the sentiment. Arthur was floored by a significant blow flush on the face in the initial stage, standing uncertainly to his feet on the referee's count.
But the red-colored attire of the fighter soon came forward again. Across the ring, the opponent - in competitive blue - was marked up early, heavy swelling developing under his eye as the duo landed punishing blows.
The challenger, 27, delivered effective strikes but the champion, 34, matched the intensity with effective uppercuts as the action rarely dropped over 12 rounds.
Arthur narrowly won the result with judges scorecards of even score, close margin and wider gap, but the two athletes were relentless and courageous, everything their hero Hatton embodied.
