British light heavyweight Buatsi secured a victory yet underwhelming debut to life under recent management with a unanimous decision over Zach Parker in Manchester.
The Olympic bronze medallist's work rate appeared to earn him a majority decision in a competitive ten-round bout at the boxing arena.
But Parker landed significant shots, delivering effective clean blows in a match where the styles failed to mesh, with excessive holding disrupting the action.
The officials judged it 96-94 for to Buatsi, with the third a 95-95.
"It wasn't my finest showing but what defines champions? They succeed," Buatsi stated in the ringside as he was faced negative reactions from the audience.
The Londoner bounced back after his initial pro loss - an memorable fight with Callum Smith in last winter - to earn a twentieth professional win.
Various analysts felt Parker, thirty-one, merited the victory but the contender endured the second defeat of his 28-match career.
The Champion Earns Victory in Dull Encounter
His career development has plateaued in the past few years through management issues and considerable time of lack of fights.
Previously predicted as the future of the British fight scene, he now is positioned trying to fulfil that early promise - possibly in what feels like a last chance - under fresh management.
He began cautiously, with neither fighter ready to take risks in a cagey opening few rounds.
The challenger, whose only previous defeat came at super middleweight against his former opponent in two years ago after breaking his hand in the contest, was competing in only his second appearance at the higher weight class.
By the middle rounds, Parker had made it competitive, making life awkward for Buatsi, who utilized a solid defense to narrowly win the better rounds.
The crowd's patience decreased during frequent holding, with Parker falling to the floor multiple occasions during close exchanges.
The underdog closed well, but many rounds were hard to judge. However, previous titleholder Carl Frampton - working with the broadcast network - had it significantly in favor for Parker, giving Buatsi just only one stanza.
Buatsi moves on, but with the likes of heavy hitter Benavidez, and Eastern European fighter Dmitry Bivol dominating the weight class, the journey to titles - based on this performance - still looks steep.
Hatton Tribute Motivates Local Rivalry Battle
In the supporting bout, Lyndon Arthur beat Rea by close verdict in a excellent Manchester vs Manchester fight to secure the European light heavyweight title.
The arena fell silent for a deeply poignant memorial ahead of the contest as ten bells rang in memory of Manchester's own Hatton, who died 46 years old in last month.
It was the first major televised fight night in the location since Hatton's passing. As the concluding sound ended, the quiet became a chant of "there's just one Hatton".
The competition inside the ropes matched the feeling. The eventual winner was floored by a significant blow directly to the chin in the second round, rising shakily to his footing on the count of eight.
But the traditional red shorts of the fighter soon advanced again. Across the ring, the opponent - in competitive blue - was damaged early, heavy swelling developing under his eye as the duo exchanged punishing blows.
Rea, twenty-seven, connected with strong blows but Arthur, 34, matched the intensity with powerful upward punches as the action hardly diminished over the full distance.
The victor barely secured the result with judges scorecards of draw, 115-113 and wider gap, but each competitor were relentless and courageous, all the qualities their idol the legend embodied.
