UK light heavyweight Buatsi earned a win yet disappointing debut to life under recent management with a decision win over Zach Parker in the Manchester arena.
The Olympic bronze medallist's punch output likely gained him a majority decision in a close ten-round contest at the Co-op Live Arena.
But Parker found success, delivering effective individual punches in a contest where the techniques didn't complement each other, with frequent clinching marring the contest.
The scoring judges judged it 96-94 for to Buatsi, with the final judge a 95-95.
"It wasn't my finest display but what do champions do? They succeed," Buatsi stated in the ringside as he was greeted with negative reactions from the crowd.
The Londoner bounced back after his first professional defeat - an thrilling contest with his previous opponent in last winter - to earn a 20th career victory.
Several boxing experts thought the challenger, 31, should have been awarded the decision but the Derbyshire fighter suffered the second setback of his 28-bout professional journey.
Buatsi Claims Victory in Dull Match
The fighter's advancement has plateaued in the past few years through promotional disputes and extended periods of inactivity.
Once tipped as the rising talent of the British fight scene, he now is positioned trying to achieve expectations - maybe in what feels like a ultimate opportunity - under new promotional backing.
He began cautiously, with the two boxers willing to be aggressive in a calculated opening few rounds.
The challenger, whose single earlier setback came at super-middleweight against John Ryder in two years ago after suffering a hand injury mid-fight, was making just his second bout at light heavyweight.
By the fight's midpoint, Parker had stayed in contention, causing problems for Buatsi, who worked behind a solid defense to narrowly win the more effective stanzas.
The spectators' acceptance diminished during frequent holding, with Parker slipping to the canvas multiple occasions during close exchanges.
Parker finished the stronger, but multiple periods were difficult to score. Nevertheless, former world champion Carl Frampton - working with Dazn - had it particularly wide for the challenger, giving Buatsi just one round.
Buatsi moves on, but with the likes of hard hitter Benavidez, and Russian champion Bivol dominating the weight class, the journey to titles - based on this performance - still seems difficult.
Hatton Memorial Motivates Manchester Derby Fight
In the secondary fight, Lyndon Arthur defeated Bradley Rea by close verdict in a outstanding Manchester vs Manchester fight to secure the European light-heavyweight title.
The venue fell silent for a extremely emotional homage prior to the bout as 10 bells sounded in honor of Manchester's own Ricky Hatton, who succumbed 46 years old in last month.
It was the initial significant broadcast match card in the city since Hatton's passing. As the last bell disappeared, the quiet became a roar of "there's only one Ricky Hatton".
The fighting during the bout reflected the feeling. The eventual winner was sent to the canvas by a left hook flush on the jaw in the second round, standing uncertainly to his feet on the referee's count.
But the red-colored attire of Arthur soon pressed ahead again. On the opposite side, the opponent - in competitive blue - was marked up early, noticeable damage forming under his orbital area as the pair landed powerful shots.
The challenger, 27, connected with strong blows but the champion, thirty-four, matched the intensity with stinging uppercuts as the pace hardly diminished over the full distance.
The victor barely secured the result with scoring tallies of draw, close margin and clearer margin, but the two athletes were relentless and courageous, everything their inspiration the legend embodied.
