British light heavyweight Buatsi secured a victory yet underwhelming debut to life under new promoters with a decision win over Zach Parker in the Manchester arena.
The Olympic medal winner's work rate seemingly secured him a majority decision in a close ten-round bout at the Manchester venue.
But the challenger had his moments, landing some telling single shots in a contest where the techniques didn't complement each other, with frequent clinching disrupting the fight.
The officials scored it 96-94 for to the winner, with the final judge a 95-95.
"It wasn't my best performance but what defines champions? They succeed," Buatsi said in the arena as he was met by negative reactions from the crowd.
The British fighter returned to winning ways after his maiden career setback - an epic battle with his previous opponent in February - to secure a 20th career victory.
Various analysts thought the challenger, 31, merited the win but the contender experienced the second setback of his 28-match career.
Buatsi Secures Triumph in Slow Match
His career development has slowed in the past few years through contract problems and extended periods of inactivity.
Previously predicted as the rising talent of British boxing, he now is positioned trying to fulfil that early promise - possibly in what seems like a ultimate opportunity - under recent support.
He began cautiously, with both competitors ready to be aggressive in a calculated early stages.
Parker, whose only previous defeat came at the lower weight class against John Ryder in two years ago after damaging his hand in the contest, was participating in his second fight at light heavyweight.
By the fight's midpoint, Parker had kept it close, causing problems for Buatsi, who operated with a solid defense to edge the more effective rounds.
The audience's tolerance diminished because of constant clinching, with Parker slipping to the canvas several times during close exchanges.
Parker ended stronger, but several stanzas were difficult to score. Although, ex-champion the boxing analyst - commentating on Dazn - had it significantly in favor for Parker, scoring for Buatsi just one round.
The victor advances, but with the presence of power puncher Benavidez, and Eastern European fighter Dmitry Bivol leading the category, the journey to titles - on this evidence - still seems difficult.
Ricky Hatton Memorial Fuels All-Manchester Battle
In the secondary fight, Lyndon Arthur beat Rea by split-decision in a outstanding all-Manchester battle to secure the European light heavyweight title.
The arena grew hushed for a extremely emotional tribute ahead of the contest as ten bells rang in honor of the city's native Hatton, who passed away 46 years old in September.
It was the first major televised fight night in the location since Hatton's death. As the final chime faded, the silence transitioned to a chant of "only one Hatton".
The competition during the bout reflected the sentiment. Arthur was floored by a powerful punch squarely on the face in the early round, getting up unsteadily to his footing on the referee's count.
But the Manchester United-red attire of Arthur soon advanced again. Across the ring, the opponent - in rival City blue - was damaged early, noticeable damage developing under his orbital area as the fighters landed hard punches.
Rea, twenty-seven, delivered effective strikes but the champion, 34, fought fire with fire with stinging uppercuts as the action hardly diminished over the full distance.
Arthur narrowly won the result with scoring tallies of 114-114, narrow lead and 115-112, but each competitor were persistent and full of heart, all the qualities their hero Hatton stood for.
