British light heavyweight Buatsi secured a victory yet underwhelming debut to life under recent management with a points victory over Zach Parker in the Manchester arena.
The Olympic medal winner's work rate likely gained him a majority decision in a tight ten-round contest at the boxing arena.
But Parker landed significant shots, delivering effective clean blows in a match where the styles failed to mesh, with frequent clinching spoiling the fight.
The scoring judges scored it 96-94 for to Buatsi, with the remaining official a 95-95.
"It wasn't my best performance but what defines champions? They win," Buatsi stated in the ring as he was met by disapproval from the crowd.
The Londoner returned to winning ways after his maiden career setback - an thrilling contest with his previous opponent in last winter - to secure a 20th career victory.
Several boxing experts thought the challenger, 31, deserved the decision but the Derbyshire fighter endured the second defeat of his 28-match career.
Buatsi Earns Win in Dull Encounter
The fighter's advancement has plateaued in the past few years through contract problems and considerable time of lack of fights.
Earlier forecast as the future of the British fight scene, he now stands trying to achieve expectations - maybe in what feels like a ultimate opportunity - under new promotional backing.
He began cautiously, with neither fighter ready to overcommit in a cagey early stages.
Parker, whose only previous defeat came at the lower weight class against John Ryder in two years ago after suffering a hand injury during the bout, was participating in his second appearance at light-heavyweight.
By the fight's midpoint, the underdog had stayed in contention, making life awkward for the favorite, who utilized a tight guard to narrowly win the cleaner stanzas.
The crowd's patience decreased because of regular grabbing, with Parker going down various instances during grappling.
Parker closed well, but many rounds were challenging to assess. Although, previous titleholder the boxing analyst - commentating on the broadcast network - had it particularly wide for Parker, awarding Buatsi just a single round.
The victor moves on, but with the likes of heavy hitter Benavidez, and Eastern European fighter Dmitry Bivol ruling the division, the journey to titles - judging by this showing - still looks steep.
Ricky Hatton Tribute Fuels Manchester Derby Contest
In the supporting bout, Arthur overcame Bradley Rea by close verdict in a excellent local rivalry fight to win the European light-heavyweight belt.
The venue became quiet for a extremely emotional tribute before the fight as a bell ceremony tolled in memory of local hero Ricky Hatton, who passed away 46 years old in recently.
It was the initial significant broadcast boxing event in the location since Hatton's passing. As the last bell disappeared, the quiet became a roar of "only one Hatton".
The action during the bout matched the emotion. Arthur was floored by a significant blow flush on the chin in the second round, getting up unsteadily to his footing on the count of eight.
But the traditional red equipment of Arthur soon advanced again. Across the ring, Rea - in opposing blue - was damaged early, heavy swelling forming under his orbital area as the pair exchanged punishing blows.
Rea, twenty-seven, connected with strong blows but Arthur, thirty-four, responded in kind with effective uppercuts as the pace seldom decreased over twelve rounds.
The victor barely secured the decision with official scores of even score, 115-113 and wider gap, but both fighters were relentless and courageous, exactly what their inspiration the legend embodied.
