UK light-heavyweight Joshua Buatsi secured a victory yet unimpressive debut to his career under new promoters with a points victory over Parker in the Manchester arena.
The Olympic medal winner's work rate likely gained him a majority decision in a competitive 10-round contest at the boxing arena.
But Parker had his moments, connecting with powerful individual punches in a fight where the techniques never quite clicked, with excessive holding disrupting the action.
The scoring judges had it 96-94 for to the winner, with the third a 95-95.
"It wasn't my finest performance but how do champions respond? They succeed," the victor commented in the ringside as he was met by boos from the spectators.
The Londoner returned to winning ways after his first professional defeat - an thrilling contest with his previous opponent in February - to earn a twentieth professional win.
Several boxing experts thought Parker, thirty-one, merited the win but the Derbyshire fighter endured the second loss of his 28-bout professional journey.
The Champion Earns Victory in Dull Match
The fighter's advancement has stalled in recent times through promotional disputes and extended periods of inactivity.
Previously predicted as the next star of UK boxing, he now finds himself trying to realize his potential - perhaps in what seems like a last chance - under fresh management.
He began cautiously, with neither fighter willing to be aggressive in a cagey opening few rounds.
Parker, whose sole prior loss came at the lower weight class against his former opponent in two years ago after damaging his hand during the bout, was making just his second bout at the higher weight class.
By the fight's midpoint, the underdog had kept it close, making life awkward for the favorite, who operated with a tight guard to narrowly win the more effective rounds.
The crowd's patience decreased during constant clinching, with Parker falling to the floor several times during clinches.
The underdog closed well, but multiple periods were hard to judge. However, ex-champion the boxing analyst - commentating on the broadcast network - had it significantly in favor for Parker, scoring for Buatsi just a single round.
Buatsi progresses, but with the caliber of heavy hitter Benavidez, and Eastern European fighter Dmitry Bivol dominating the weight class, the road to world glory - based on this performance - still seems difficult.
Ricky Hatton Tribute Inspires All-Manchester Contest
In the secondary fight, Arthur overcame Bradley Rea by close verdict in a outstanding all-Manchester battle to capture the European light-heavyweight belt.
The stadium fell silent for a profoundly moving homage before the fight as 10 bells rang in remembrance of Manchester's own Hatton, who succumbed at age 46 in recently.
It was the premier televised match card in the city since Hatton's death. As the concluding sound ended, the silence became a shout of "only one Ricky Hatton".
The action within the ring matched the sentiment. Arthur was knocked down by a left hook directly to the chin in the second round, getting up unsteadily to his position on the referee's count.
But the Manchester United-red attire of Arthur soon pressed ahead again. Across the ring, the opponent - in opposing blue - was injured early, significant bruising developing under his eye as the duo exchanged hard punches.
The challenger, twenty-seven, delivered effective strikes but the champion, thirty-four, fought fire with fire with effective uppercuts as the pace rarely dropped over twelve rounds.
The victor edged the decision with judges scorecards of draw, 115-113 and clearer margin, but the two athletes were persistent and courageous, exactly what their hero the legend embodied.
