British light heavyweight Buatsi earned a win yet underwhelming start to life under fresh promotional backing with a decision win over Zach Parker in the Manchester arena.
The Olympic medal winner's work rate appeared to earn him a majority decision in a competitive ten-round bout at the Co-op Live Arena.
But Parker had his moments, landing some telling individual punches in a contest where the techniques never quite clicked, with frequent clinching marring the action.
The scoring judges judged it 96-94 for to Buatsi, with the third a even score.
"It wasn't my greatest showing but how do champions respond? They win," Buatsi commented in the arena as he was met by boos from the audience.
The British fighter bounced back after his maiden career setback - an memorable fight with his previous opponent in last winter - to claim a twentieth professional win.
Various analysts thought the challenger, thirty-one, should have been awarded the victory but the Derbyshire fighter suffered the second setback of his 28-match professional journey.
The Champion Secures Victory in Uneventful Affair
His career development has slowed in the past few years through promotional disputes and long spells of inactivity.
Earlier forecast as the rising talent of UK boxing, he now finds himself trying to achieve expectations - maybe in what seems like a final roll of the dice - under fresh management.
He began cautiously, with neither fighter willing to take risks in a tentative opening few rounds.
The challenger, whose single earlier setback came at the lower weight class against John Ryder in two years ago after suffering a hand injury mid-fight, was competing in only his second bout at light-heavyweight.
By the fight's midpoint, Parker had stayed in contention, creating difficulties for the favorite, who operated with a protective stance to narrowly win the better rounds.
The audience's tolerance diminished because of frequent holding, with Parker slipping to the canvas multiple occasions during clinches.
Parker finished the stronger, but many rounds were difficult to score. However, former world champion Carl Frampton - providing analysis for Dazn - had it significantly in favor for Parker, giving Buatsi just only one stanza.
The victor progresses, but with the presence of heavy hitter Benavidez, and Eastern European fighter Bivol dominating the weight class, the journey to titles - on this evidence - still looks steep.
Hatton Memorial Inspires All-Manchester Fight
In the co-main event, Arthur defeated Bradley Rea by split-decision in a excellent local rivalry battle to win the European light heavyweight championship.
The arena fell silent for a profoundly moving memorial before the fight as 10 bells rang in memory of local hero Ricky Hatton, who passed away aged 46 in last month.
It was the initial significant broadcast match card in the city since Hatton's death. As the last bell faded, the stillness became a shout of "there's just one Hatton".
The competition during the bout equaled the emotion. The eventual winner was sent to the canvas by a significant blow flush on the jaw in the early round, getting up unsteadily to his footing on the eight count.
But the traditional red attire of the fighter soon pressed ahead again. On the opposite side, Rea - in rival City blue - was marked up early, noticeable damage forming under his orbital area as the duo traded punishing blows.
The challenger, 27, delivered effective strikes but the champion, 34, fought fire with fire with stinging uppercuts as the intensity seldom decreased over the full distance.
The victor narrowly won the result with scoring tallies of 114-114, close margin and 115-112, but the two athletes were persistent and full of heart, everything their idol the legend embodied.
