UK light-heavyweight Joshua Buatsi earned a win yet underwhelming beginning to his career under fresh promotional backing with a points victory over Parker in the Manchester arena.
The Olympic medal winner's punch output appeared to earn him a split decision in a competitive ten-round contest at the boxing arena.
But the challenger had his moments, delivering effective individual punches in a match where the approaches failed to mesh, with constant grabbing disrupting the contest.
The scoring judges judged it 96-94 to Buatsi, with the third a even score.
"It wasn't my finest showing but how do champions respond? They succeed," Buatsi stated in the ringside as he was greeted with boos from the crowd.
The British fighter bounced back after his initial pro loss - an thrilling contest with his previous opponent in last winter - to earn a 20th career victory.
Several boxing experts felt Parker, thirty-one, deserved the win but the Derbyshire fighter endured the second loss of his 28-bout professional journey.
Buatsi Earns Win in Slow Match
His career development has stalled in recent years through contract problems and long spells of lack of fights.
Earlier forecast as the future of the British fight scene, he now finds himself trying to fulfil that early promise - perhaps in what appears to be a last chance - under fresh management.
He started carefully, with both competitors ready to take risks in a calculated opening few rounds.
The challenger, whose single earlier setback came at super middleweight against his former opponent in two years ago after damaging his hand mid-fight, was making just his second bout at light heavyweight.
By the fight's midpoint, the underdog had stayed in contention, creating difficulties for the favorite, who operated with a solid defense to edge the better rounds.
The spectators' acceptance decreased because of constant clinching, with Parker slipping to the canvas multiple occasions during grappling.
The underdog ended stronger, but many rounds were difficult to score. However, former world champion the boxing analyst - commentating on Dazn - had it particularly wide for the challenger, scoring for Buatsi just one round.
Buatsi progresses, but with the caliber of hard hitter Benavidez, and Eastern European fighter Dmitry Bivol dominating the weight class, the road to world glory - judging by this showing - still looks steep.
Ricky Hatton Homage Inspires Manchester Derby Fight
In the supporting bout, Arthur beat Bradley Rea by split-decision in a excellent local rivalry contest to secure the continental belt.
The arena grew hushed for a extremely emotional homage prior to the bout as a bell ceremony rang in memory of Manchester's own Ricky Hatton, who succumbed 46 years old in recently.
It was the premier televised fight night in the city since Hatton's passing. As the final chime faded, the silence became a shout of "only one Hatton".
The action inside the ropes equaled the emotion. Arthur was sent to the canvas by a significant blow squarely on the face in the second round, standing uncertainly to his footing on the eight count.
But the traditional red attire of Arthur soon advanced again. On the opposite side, Rea - in competitive blue - was marked up quickly, noticeable damage forming under his face as the pair landed hard punches.
Rea, twenty-seven, delivered effective strikes but Arthur, 34, matched the intensity with powerful upward punches as the intensity seldom decreased over 12 rounds.
The victor narrowly won the verdict with judges scorecards of even score, narrow lead and wider gap, but the two athletes were relentless and brave, everything their idol the legend represented.
