UK light heavyweight Joshua Buatsi secured a victory yet unimpressive debut to his career under recent management with a points victory over Parker in the Manchester arena.
The Olympic bronze medallist's punch output likely gained him a split decision in a competitive 10-round bout at the boxing arena.
But Parker landed significant shots, landing some telling individual punches in a fight where the approaches never quite clicked, with constant grabbing spoiling the fight.
The scoring judges scored it 96-94 to Buatsi, with the final judge a 95-95 draw.
"It wasn't my best display but how do champions respond? They prevail," Buatsi said in the ring as he was greeted with negative reactions from the audience.
The Londoner bounced back after his first professional defeat - an memorable fight with his previous opponent in last winter - to earn a twentieth professional win.
Several boxing experts believed the challenger, thirty-one, merited the win but the contender experienced the second setback of his 28-fight career.
Buatsi's progress has slowed in recent years through management issues and considerable time of inactivity.
Once tipped as the rising talent of UK boxing, he now is positioned trying to realize his potential - maybe in what seems like a ultimate opportunity - under recent support.
He opened tentatively, with both competitors prepared to be aggressive in a tentative opening few rounds.
Parker, whose sole prior loss came at the lower weight class against his former opponent in two years ago after breaking his hand during the bout, was competing in only his second fight at the higher weight class.
By the fight's midpoint, the underdog had made it competitive, causing problems for the favorite, who utilized a protective stance to barely take the more effective stanzas.
The audience's tolerance diminished during frequent holding, with Parker falling to the floor multiple occasions during clinches.
Parker ended stronger, but several stanzas were difficult to score. However, former world champion Carl Frampton - working with the broadcast network - had it particularly wide for the challenger, scoring for Buatsi just one round.
The victor moves on, but with the presence of hard hitter Benavidez, and Eastern European fighter Bivol ruling the division, the road to world glory - on this evidence - still looks steep.
In the supporting bout, Lyndon Arthur overcame Rea by split-decision in a outstanding local rivalry battle to secure the European light-heavyweight title.
The stadium became quiet for a deeply poignant memorial before the fight as 10 bells rang in memory of local hero Hatton, who died at age 46 in last month.
It was the initial significant broadcast fight night in the location since Hatton's death. As the concluding sound faded, the quiet transitioned to a shout of "there's just one Hatton".
The competition during the bout equaled the emotion. Arthur was knocked down by a powerful punch flush on the face in the second round, rising shakily to his feet on the count of eight.
But the red-colored equipment of Arthur soon came forward again. From the other corner, the opponent - in competitive blue - was marked up early, heavy swelling forming under his face as the duo traded hard punches.
The challenger, 27, landed power punches but the champion, thirty-four, fought fire with fire with effective uppercuts as the intensity hardly diminished over the full distance.
Arthur edged the verdict with scoring tallies of 114-114, close margin and clearer margin, but the two athletes were persistent and full of heart, all the qualities their inspiration the legend embodied.
Elara is a tech journalist with a decade of experience covering software development and digital innovation trends.