UK light-heavyweight Buatsi secured a victory yet underwhelming start to his career under recent management with a unanimous decision over Zach Parker in Manchester.
The Olympic medal winner's work rate seemingly secured him a judges' verdict in a close ten-round contest at the Co-op Live Arena.
But the challenger found success, delivering effective individual punches in a match where the techniques didn't complement each other, with constant grabbing disrupting the fight.
The scoring judges judged it 96-94 in favor to the winner, with the third a even score.
"It wasn't my finest performance but what do champions do? They succeed," the victor said in the ring as he was faced negative reactions from the audience.
The British fighter returned to winning ways after his first professional defeat - an thrilling contest with his previous opponent in last winter - to earn a twentieth professional win.
Various analysts thought the challenger, 31, merited the decision but the British boxer experienced the second setback of his 28-bout professional journey.
Buatsi Earns Win in Uneventful Affair
Buatsi's progress has stalled in the past few years through management issues and long spells of lack of fights.
Once tipped as the future of the British fight scene, he now stands trying to fulfil that early promise - perhaps in what feels like a ultimate opportunity - under new promotional backing.
He started carefully, with the two boxers ready to overcommit in a tentative opening few rounds.
Parker, whose only previous defeat came at super-middleweight against his former opponent in 2022 after breaking his hand mid-fight, was making just his second appearance at the higher weight class.
By the fight's midpoint, Parker had made it competitive, creating difficulties for Buatsi, who worked behind a tight guard to edge the more effective stanzas.
The audience's tolerance wore thin amid regular grabbing, with Parker slipping to the canvas several times during close exchanges.
Parker finished the stronger, but multiple periods were challenging to assess. However, previous titleholder the boxing analyst - providing analysis for Dazn - had it significantly in favor for the challenger, scoring for Buatsi just only one stanza.
The victor moves on, but with the presence of hard hitter Benavidez, and Russian star Bivol leading the category, the road to world glory - judging by this showing - still appears challenging.
Ricky Hatton Homage Inspires All-Manchester Battle
In the co-main event, Arthur overcame Rea by divided decision in a excellent all-Manchester fight to secure the European light heavyweight belt.
The venue became quiet for a extremely emotional homage before the fight as 10 bells rang in memory of Manchester's own Ricky Hatton, who succumbed aged 46 in last month.
It was the premier televised boxing event in the city since Hatton's death. As the last bell ended, the stillness transitioned to a roar of "there's just one Hatton".
The fighting inside the ropes matched the feeling. The eventual winner was knocked down by a left hook directly to the chin in the early round, rising shakily to his footing on the referee's count.
But the traditional red equipment of Arthur soon advanced again. Across the ring, the opponent - in opposing blue - was damaged quickly, significant bruising appearing under his eye as the fighters traded powerful shots.
The challenger, twenty-seven, connected with strong blows but Arthur, 34, matched the intensity with effective uppercuts as the pace rarely dropped over twelve rounds.
Arthur barely secured the decision with official scores of 114-114, close margin and wider gap, but each competitor were determined and full of heart, everything their idol Hatton represented.
