British light-heavyweight Joshua Buatsi earned a win yet unimpressive start to his career under recent management with a points victory over Parker in Manchester.
The Olympic bronze medallist's work rate seemingly secured him a judges' verdict in a close 10-round bout at the Manchester venue.
But the challenger had his moments, delivering effective single shots in a match where the styles failed to mesh, with frequent clinching marring the action.
The scoring judges had it 96-94 to the winner, with the remaining official a even score.
"It wasn't my best performance but what do champions do? They win," the victor commented in the ring as he was greeted with disapproval from the spectators.
The Londoner got back to winning after his initial pro loss - an thrilling contest with his previous opponent in last winter - to claim a 20th pro success.
Some ringside observers felt the challenger, thirty-one, merited the win but the contender endured the second defeat of his 28-fight professional journey.
Buatsi Claims Triumph in Slow Match
The fighter's advancement has stalled in recent times through management issues and extended periods of lack of fights.
Previously predicted as the future of the British fight scene, he now finds himself trying to realize his potential - maybe in what seems like a final roll of the dice - under fresh management.
He started carefully, with the two boxers willing to take risks in a cagey early stages.
The challenger, whose sole prior loss came at the lower weight class against his former opponent in 2022 after suffering a hand injury in the contest, was participating in his second appearance at light heavyweight.
By the middle rounds, the underdog had made it competitive, creating difficulties for the favorite, who utilized a tight guard to narrowly win the better periods.
The crowd's patience wore thin during regular grabbing, with Parker falling to the floor multiple occasions during grappling.
Parker ended stronger, but multiple periods were challenging to assess. Nevertheless, former world champion Carl Frampton - commentating on Dazn - had it significantly in favor for Parker, giving Buatsi just one round.
The victor moves on, but with the caliber of heavy hitter Benavidez, and Russian star Dmitry Bivol leading the category, the road to world glory - based on this performance - still appears challenging.
Hatton Memorial Fuels All-Manchester Fight
In the co-main event, Arthur beat Rea by divided decision in a excellent local rivalry battle to capture the continental belt.
The stadium fell silent for a profoundly moving tribute ahead of the contest as ten bells rang in memory of Manchester's own Hatton, who succumbed 46 years old in September.
It was the premier televised boxing event in the location since Hatton's death. As the final chime disappeared, the quiet transitioned to a chant of "there's only one Ricky Hatton".
The competition during the bout matched the sentiment. The eventual winner was floored by a powerful punch squarely on the jaw in the second round, standing uncertainly to his position on the count of eight.
But the Manchester United-red attire of the fighter soon advanced again. On the opposite side, the opponent - in opposing blue - was marked up soon, significant bruising appearing under his face as the duo landed punishing blows.
Rea, twenty-seven, connected with strong blows but Arthur, thirty-four, responded in kind with powerful upward punches as the pace hardly diminished over the full distance.
The victor barely secured the result with official scores of even score, narrow lead and clearer margin, but the two athletes were persistent and brave, exactly what their inspiration Hatton embodied.
