British light-heavyweight Buatsi earned a win yet unimpressive beginning to life under recent management with a unanimous decision over Zach Parker in the Manchester arena.
The Olympic bronze medallist's activity level likely gained him a split decision in a tight 10-round contest at the Manchester venue.
But Parker found success, landing some telling single shots in a contest where the styles never quite clicked, with frequent clinching disrupting the action.
The scoring judges scored it 96-94 in favor to the winner, with the third a 95-95.
"It wasn't my finest display but how do champions respond? They prevail," the victor said in the ringside as he was faced negative reactions from the spectators.
The British fighter returned to winning ways after his initial pro loss - an memorable fight with Callum Smith in last winter - to claim a 20th pro success.
Several boxing experts felt the challenger, thirty-one, should have been awarded the decision but the British boxer experienced the second setback of his 28-bout professional journey.
The Champion Earns Victory in Uneventful Encounter
The fighter's advancement has plateaued in recent years through management issues and long spells of inactivity.
Once tipped as the next star of British boxing, he now is positioned trying to achieve expectations - maybe in what seems like a final roll of the dice - under fresh management.
He started carefully, with the two boxers willing to overcommit in a calculated initial rounds.
Parker, whose only previous defeat came at the lower weight class against John Ryder in 2022 after breaking his hand mid-fight, was participating in his second fight at the higher weight class.
By the fight's midpoint, the underdog had stayed in contention, causing problems for Buatsi, who worked behind a tight guard to narrowly win the more effective rounds.
The spectators' acceptance decreased during frequent holding, with Parker slipping to the canvas multiple occasions during grappling.
Parker ended stronger, but multiple periods were hard to judge. Nevertheless, former world champion Carl Frampton - working with Dazn - had it particularly wide for the challenger, giving Buatsi just one round.
Buatsi advances, but with the likes of hard hitter Benavidez, and Eastern European fighter Bivol ruling the division, the road to world glory - judging by this showing - still looks steep.
Hatton Homage Inspires Local Rivalry Contest
In the co-main event, Lyndon Arthur defeated Rea by split-decision in a outstanding all-Manchester contest to win the European light heavyweight title.
The stadium grew hushed for a profoundly moving memorial before the fight as a bell ceremony tolled in memory of Manchester's own Hatton, who passed away aged 46 in September.
It was the initial significant broadcast match card in the location since the passing of Hatton. As the last bell disappeared, the stillness gave way to a shout of "there's just one Ricky Hatton".
The fighting within the ring equaled the sentiment. Arthur was floored by a powerful punch squarely on the jaw in the second round, getting up unsteadily to his feet on the referee's count.
But the Manchester United-red attire of the fighter soon advanced again. On the opposite side, the opponent - in competitive blue - was marked up quickly, heavy swelling forming under his eye as the duo exchanged punishing blows.
The challenger, twenty-seven, delivered effective strikes but the champion, 34, fought fire with fire with powerful upward punches as the action seldom decreased over twelve rounds.
The victor barely secured the result with official scores of 114-114, 115-113 and wider gap, but both fighters were persistent and full of heart, exactly what their hero the legend embodied.
