British light heavyweight Buatsi earned a win yet unimpressive debut to life under recent management with a unanimous decision over Zach Parker in the Manchester arena.
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 the challenger had his moments, connecting with powerful clean blows in a contest where the styles never quite clicked, with constant grabbing disrupting the fight.
Two judges had it 96-94 in favor to the winner, with the final judge a even score.
"It wasn't my finest showing but how do champions respond? They win," Buatsi said in the arena as he was faced negative reactions from the crowd.
The British fighter bounced back after his first professional defeat - an memorable fight with his previous opponent in February - to secure a twentieth professional win.
Various analysts believed the challenger, thirty-one, merited the victory but the contender endured the second loss of his 28-fight professional journey.
Buatsi Claims Triumph in Uneventful Encounter
His career development has stalled in the past few years through promotional disputes and extended periods of inactivity.
Previously predicted as the next star of UK boxing, he now is positioned trying to achieve expectations - perhaps in what feels like a ultimate opportunity - under new promotional backing.
He started carefully, with both competitors willing to overcommit in a cagey opening few rounds.
Parker, whose only previous defeat came at super-middleweight against John Ryder in 2022 after suffering a hand injury during the bout, was competing in only his second bout at the higher weight class.
By the middle rounds, Parker had stayed in contention, creating difficulties for the favorite, who utilized a protective stance to barely take the better stanzas.
The audience's tolerance diminished amid frequent holding, with the challenger slipping to the canvas various instances during grappling.
The underdog finished the stronger, but many rounds were challenging to assess. Nevertheless, previous titleholder Carl Frampton - providing analysis for Dazn - had it strongly leaning for Parker, giving Buatsi just one round.
The victor moves on, but with the caliber of heavy hitter David Benavidez, and Russian champion Bivol ruling the division, the journey to titles - judging by this showing - still looks steep.
Hatton Memorial Fuels Manchester Derby Battle
In the supporting bout, Lyndon Arthur defeated Rea by split-decision in a excellent local rivalry contest to capture the European light-heavyweight belt.
The stadium became quiet for a deeply poignant memorial ahead of the contest as ten bells rang in memory of Manchester's own Ricky Hatton, who succumbed 46 years old in recently.
It was the initial significant broadcast fight night in the location since Hatton's passing. As the concluding sound ended, the silence gave way to a chant of "there's only one Ricky Hatton".
The competition during the bout reflected the emotion. The eventual winner was floored by a significant blow squarely on the chin in the second round, getting up unsteadily to his footing on the count of eight.
But the Manchester United-red attire of Arthur soon came forward again. Across the ring, the opponent - in competitive blue - was damaged soon, heavy swelling appearing under his eye as the pair landed punishing blows.
The challenger, 27, landed power punches but Arthur, thirty-four, responded in kind with stinging uppercuts as the intensity rarely dropped over 12 rounds.
The victor barely secured the result with judges scorecards of draw, 115-113 and 115-112, but each competitor were relentless and courageous, everything their inspiration the legend stood for.
