UK light heavyweight Buatsi secured a victory yet underwhelming debut to life under recent management with a decision win over Zach Parker in Manchester.
The Olympic bronze medallist's work rate seemingly secured him a judges' verdict in a close 10-round contest at the Co-op Live Arena.
But Parker landed significant shots, connecting with powerful clean blows in a contest where the approaches didn't complement each other, with frequent clinching marring the contest.
The scoring judges had it 96-94 in favor to the winner, with the remaining official a 95-95 draw.
"It wasn't my greatest display but what do champions do? They win," the victor commented in the ringside as he was greeted with negative reactions from the crowd.
The British fighter bounced back after his initial pro loss - an memorable fight with Callum Smith in last winter - to earn a twentieth professional win.
Various analysts believed the challenger, thirty-one, deserved the decision but the British boxer experienced the second loss of his 28-fight professional journey.
The Champion Earns Triumph in Slow Affair
Buatsi's progress has plateaued in the past few years through contract problems and extended periods of inactivity.
Once tipped as the next star of British boxing, he now stands trying to fulfil that early promise - perhaps in what feels like a ultimate opportunity - under fresh management.
He opened tentatively, with the two boxers ready to take risks in a cagey early stages.
The challenger, whose single earlier setback came at super-middleweight against John Ryder in 2022 after damaging his hand in the contest, was competing in only his second bout at light-heavyweight.
By the fight's midpoint, Parker had made it competitive, making life awkward for Buatsi, who worked behind a solid defense to barely take the cleaner stanzas.
The spectators' acceptance decreased amid constant clinching, with the challenger falling to the floor several times during clinches.
Parker closed well, but several stanzas were difficult to score. Nevertheless, former world champion the boxing analyst - commentating on the broadcast network - had it particularly wide for the challenger, scoring for Buatsi just one round.
Buatsi moves on, but with the likes of heavy hitter Benavidez, and Russian champion Dmitry Bivol ruling the division, the journey to titles - judging by this showing - still seems difficult.
Hatton Tribute Inspires Manchester Derby Fight
In the co-main event, Arthur beat Bradley Rea by divided decision in a outstanding local rivalry fight to secure the European light heavyweight championship.
The stadium grew hushed for a extremely emotional memorial before the fight as a bell ceremony tolled in honor of Manchester's own Ricky Hatton, who succumbed aged 46 in recently.
It was the premier televised fight night in the location since Hatton's death. As the last bell ended, the silence became a shout of "there's just one Ricky Hatton".
The competition within the ring equaled the sentiment. Arthur was knocked down by a left hook directly to the jaw in the early round, rising shakily to his position on the count of eight.
But the red-colored attire of the fighter soon came forward again. On the opposite side, Rea - in rival City blue - was marked up quickly, noticeable damage developing under his eye as the duo traded hard punches.
Rea, twenty-seven, connected with strong blows but the champion, thirty-four, fought fire with fire with powerful upward punches as the intensity hardly diminished over twelve rounds.
Arthur narrowly won the decision with official scores of even score, close margin and wider gap, but the two athletes were relentless and brave, all the qualities their idol Hatton embodied.
