UK light heavyweight Buatsi secured a victory yet disappointing start to his career under fresh promotional backing with a decision win over Zach Parker in Manchester.
The Olympic bronze medallist's punch output likely gained him a majority decision in a competitive 10-round contest at the Manchester venue.
But Parker landed significant shots, landing some telling single shots in a match where the styles never quite clicked, with constant grabbing marring the contest.
The scoring judges judged it 96-94 in favor to the winner, with the final judge a 95-95.
"It wasn't my best performance but how do champions respond? They prevail," Buatsi stated in the ring as he was greeted with negative reactions from the audience.
The British fighter returned to winning ways after his first professional defeat - an epic battle with his previous opponent in last winter - to claim a 20th pro success.
Some ringside observers thought the challenger, thirty-one, should have been awarded the win but the contender experienced the second loss of his 28-match career.
Buatsi Secures Win in Dull Affair
His career development has plateaued in recent times through promotional disputes and long spells of inactivity.
Earlier forecast as the next star of British boxing, he now is positioned trying to achieve expectations - perhaps in what seems like a final roll of the dice - under recent support.
He began cautiously, with neither fighter prepared to take risks in a calculated initial rounds.
Parker, whose only previous defeat came at super-middleweight against his former opponent in two years ago after damaging his hand mid-fight, was competing in only his second bout at light-heavyweight.
By the halfway stage, the underdog had made it competitive, creating difficulties for Buatsi, who operated with a tight guard to barely take the cleaner stanzas.
The crowd's patience wore thin during regular grabbing, with Parker slipping to the canvas several times during close exchanges.
The underdog ended stronger, but multiple periods were difficult to score. Although, ex-champion the boxing analyst - providing analysis for the broadcast network - had it particularly wide for Parker, scoring for Buatsi just a single round.
Buatsi moves on, but with the caliber of heavy hitter Benavidez, and Russian star Dmitry Bivol dominating the weight class, the path to championship success - judging by this showing - still seems difficult.
Hatton Homage Inspires Local Rivalry Battle
In the secondary fight, Lyndon Arthur beat Rea by close verdict in a excellent local rivalry fight to secure the European light-heavyweight belt.
The stadium became quiet for a profoundly moving memorial ahead of the contest as a bell ceremony rang in honor of local hero Hatton, who succumbed at age 46 in September.
It was the initial significant broadcast fight night in the urban center since the passing of Hatton. As the concluding sound disappeared, the quiet gave way to a roar of "there's just one Ricky Hatton".
The fighting within the ring matched the feeling. Arthur was sent to the canvas by a significant blow squarely on the jaw in the early round, getting up unsteadily to his position on the count of eight.
But the traditional red shorts of the fighter soon came forward again. On the opposite side, the opponent - in rival City blue - was marked up early, heavy swelling developing under his eye as the duo traded punishing blows.
The challenger, twenty-seven, connected with strong blows but the champion, thirty-four, matched the intensity with effective uppercuts as the intensity seldom decreased over 12 rounds.
The victor narrowly won the verdict with official scores of draw, close margin and 115-112, but both fighters were relentless and brave, exactly what their hero Hatton stood for.
