British light heavyweight Buatsi earned a win yet unimpressive beginning to life under fresh promotional backing with a decision win over Zach Parker in Manchester.
The Olympic bronze medallist's punch output seemingly secured him a majority decision in a tight ten-round contest at the Co-op Live Arena.
But Parker had his moments, landing some telling single shots in a match where the approaches never quite clicked, with frequent clinching marring the fight.
The officials scored it 96-94 to Buatsi, with the final judge a 95-95.
"It wasn't my greatest display but what defines champions? They prevail," Buatsi said in the ring as he was faced negative reactions from the spectators.
The British fighter got back to winning after his initial pro loss - an thrilling contest with Callum Smith in last winter - to claim a twentieth professional win.
Various analysts believed the challenger, thirty-one, merited the win but the British boxer experienced the second setback of his 28-fight professional journey.
The Champion Earns Win in Uneventful Encounter
Buatsi's progress has slowed in recent times through promotional disputes and considerable time of lack of fights.
Earlier forecast as the future of the British fight scene, he now finds himself trying to realize his potential - maybe in what seems like a last chance - under fresh management.
He began cautiously, with both competitors ready to overcommit in a cagey initial rounds.
The challenger, whose only previous defeat came at super-middleweight against John Ryder in two years ago after breaking his hand during the bout, was making just his second fight at the higher weight class.
By the fight's midpoint, the underdog had kept it close, creating difficulties for the favorite, who operated with a protective stance to narrowly win the more effective rounds.
The audience's tolerance decreased during constant clinching, with the challenger going down multiple occasions during grappling.
Parker finished the stronger, but multiple periods were challenging to assess. However, previous titleholder Carl Frampton - commentating on Dazn - had it particularly wide for the challenger, scoring for Buatsi just one round.
Buatsi progresses, but with the caliber of heavy hitter Benavidez, and Russian champion Bivol dominating the weight class, the path to championship success - judging by this showing - still appears challenging.
Hatton Homage Motivates Local Rivalry Contest
In the co-main event, Lyndon Arthur defeated Bradley Rea by divided decision in a excellent local rivalry battle to win the European light heavyweight title.
The venue became quiet for a profoundly moving homage ahead of the contest as a bell ceremony rang in honor of Manchester's own Ricky Hatton, who passed away aged 46 in September.
It was the first major televised match card in the urban center since Hatton's passing. As the last bell faded, the quiet gave way to a shout of "there's only one Ricky Hatton".
The competition inside the ropes equaled the sentiment. The eventual winner was knocked down by a left hook squarely on the jaw in the early round, standing uncertainly to his position on the referee's count.
But the red-colored shorts of the fighter soon pressed ahead again. On the opposite side, the opponent - in opposing blue - was injured quickly, significant bruising forming under his orbital area as the fighters exchanged powerful shots.
Rea, 27, landed power punches but Arthur, 34, responded in kind with effective uppercuts as the pace hardly diminished over 12 rounds.
Arthur narrowly won the verdict with scoring tallies of even score, 115-113 and wider gap, but both fighters were persistent and brave, exactly what their inspiration Hatton embodied.
