British light heavyweight Buatsi earned a win yet underwhelming start to life under recent management with a unanimous decision over Zach Parker in the Manchester arena.
The Olympic bronze medallist's punch output appeared to earn him a majority decision in a close ten-round fight at the Manchester venue.
But the challenger had his moments, landing some telling single shots in a match where the styles didn't complement each other, with frequent clinching spoiling the action.
The scoring judges judged it 96-94 for to Buatsi, with the remaining official a 95-95.
"It wasn't my best performance but how do champions respond? They prevail," Buatsi commented in the ringside as he was met by boos from the audience.
The British fighter returned to winning ways after his initial pro loss - an memorable fight with his previous opponent in February - to claim a 20th career victory.
Several boxing experts felt the challenger, thirty-one, should have been awarded the decision but the Derbyshire fighter experienced the second setback of his 28-bout professional journey.
The Champion Claims Win in Dull Affair
Buatsi's progress has slowed in recent years through management issues and extended periods of inactivity.
Earlier forecast as the rising talent of the British fight scene, he now stands trying to fulfil that early promise - possibly in what seems like a final roll of the dice - under fresh management.
He started carefully, with both competitors prepared to be aggressive in a tentative 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 participating in his second fight at light heavyweight.
By the middle rounds, the underdog had stayed in contention, causing problems for Buatsi, who utilized a tight guard to barely take the cleaner rounds.
The crowd's patience wore thin because of frequent holding, with the challenger going down multiple occasions during close exchanges.
The underdog ended stronger, but many rounds were challenging to assess. However, previous titleholder Carl Frampton - commentating on the broadcast network - had it particularly wide for the challenger, giving Buatsi just a single round.
The victor progresses, but with the likes of hard hitter David Benavidez, and Eastern European fighter Dmitry Bivol ruling the division, the journey to titles - on this evidence - still appears challenging.
Hatton Homage Motivates All-Manchester Battle
In the secondary fight, Arthur defeated Bradley Rea by close verdict in a outstanding all-Manchester battle to capture the European light heavyweight belt.
The venue became quiet for a extremely emotional homage ahead of the contest as 10 bells tolled in honor of the city's native Hatton, who succumbed 46 years old in September.
It was the premier televised fight night in the urban center since Hatton's passing. As the final chime faded, the quiet gave way to a roar of "only one Hatton".
The action within the ring equaled the emotion. Arthur was sent to the canvas by a left hook squarely on the jaw in the initial stage, standing uncertainly to his position on the count of eight.
But the red-colored shorts of Arthur soon pressed ahead again. From the other corner, Rea - in competitive blue - was marked up early, significant bruising developing under his eye as the fighters landed powerful shots.
The challenger, 27, delivered effective strikes but the champion, thirty-four, matched the intensity with stinging uppercuts as the pace hardly diminished over 12 rounds.
Arthur narrowly won the decision with scoring tallies of 114-114, close margin and 115-112, but both fighters were persistent and brave, all the qualities their inspiration Hatton represented.
