British light-heavyweight Joshua Buatsi made a winning yet underwhelming start to his career under new promoters with a points victory over Parker in Manchester.
The Olympic medal winner's punch output appeared to earn him a judges' verdict in a tight ten-round fight at the boxing arena.
But Parker found success, delivering effective single shots in a match where the approaches never quite clicked, with frequent clinching disrupting the contest.
The scoring judges had it 96-94 to the winner, with the third a even score.
"It wasn't my best display but what defines champions? They prevail," the victor commented in the arena as he was faced disapproval from the crowd.
The British fighter returned to winning ways after his maiden career setback - an epic battle with his previous opponent in February - to claim a twentieth professional win.
Various analysts believed Parker, 31, should have been awarded the decision but the Derbyshire fighter endured the second setback of his 28-fight professional journey.
Buatsi Earns Win in Slow Match
His career development has stalled in recent times through management issues and extended periods of inactivity.
Earlier forecast as the rising talent of UK boxing, he now stands trying to fulfil that early promise - maybe in what seems like a final roll of the dice - under new promotional backing.
He began cautiously, with the two boxers ready to take risks in a calculated initial rounds.
Parker, whose single earlier setback came at super-middleweight against his former opponent in two years ago after breaking his hand during the bout, was competing in only his second appearance at light heavyweight.
By the fight's midpoint, Parker had kept it close, causing problems for the favorite, who worked behind a solid defense to edge the better stanzas.
The crowd's patience decreased during regular grabbing, with Parker going down various instances during grappling.
Parker finished the stronger, but many rounds were challenging to assess. Nevertheless, ex-champion Carl Frampton - providing analysis for the broadcast network - had it strongly leaning for the challenger, awarding Buatsi just a single round.
Buatsi moves on, but with the presence of heavy hitter Benavidez, and Russian champion Dmitry Bivol leading the category, the road to world glory - on this evidence - still appears challenging.
Ricky Hatton Tribute Fuels Manchester Derby Contest
In the co-main event, Lyndon Arthur beat Bradley Rea by split-decision in a outstanding Manchester vs Manchester contest to secure the continental title.
The arena became quiet for a extremely emotional tribute prior to the bout as a bell ceremony rang in honor of local hero Hatton, who passed away 46 years old in September.
It was the initial significant broadcast match card in the urban center since Hatton's passing. As the concluding sound ended, the stillness transitioned to a chant of "there's just one Hatton".
The action during the bout equaled the sentiment. Arthur was sent to the canvas by a powerful punch directly to the face in the initial stage, rising shakily to his feet on the count of eight.
But the red-colored shorts of the fighter soon came forward again. Across the ring, the opponent - in rival City blue - was marked up quickly, significant bruising forming under his orbital area as the fighters traded powerful shots.
Rea, 27, delivered effective strikes but Arthur, thirty-four, fought fire with fire with powerful upward punches as the action hardly diminished over the full distance.
Arthur barely secured the result with official scores of 114-114, 115-113 and wider gap, but both fighters were determined and full of heart, all the qualities their inspiration Hatton stood for.
