UK light heavyweight Joshua Buatsi earned a win yet underwhelming debut to his career under fresh promotional backing with a decision win over Parker in Manchester.
The Olympic medal winner's punch output seemingly secured him a split decision in a close ten-round contest at the Manchester venue.
But Parker landed significant shots, connecting with powerful single shots in a contest where the techniques failed to mesh, with constant grabbing disrupting the fight.
The scoring judges scored it 96-94 in favor to the winner, with the remaining official a even score.
"It wasn't my greatest showing but what do champions do? They win," Buatsi commented in the ringside as he was faced disapproval from the audience.
The Londoner got back to winning after his maiden career setback - an epic battle with his previous opponent in February - to claim a twentieth professional win.
Some ringside observers felt the challenger, thirty-one, deserved the win but the Derbyshire fighter suffered the second setback of his 28-fight career.
Buatsi Claims Victory in Uneventful Affair
Buatsi's progress has slowed in recent years through promotional disputes and considerable time of lack of fights.
Previously predicted as the future of the British fight scene, he now is positioned trying to realize his potential - maybe in what feels like a final roll of the dice - under fresh management.
He began cautiously, with both competitors prepared to take risks in a cagey early stages.
The challenger, whose sole prior loss came at super-middleweight against John Ryder in two years ago after breaking his hand in the contest, was making just his second fight at light-heavyweight.
By the middle rounds, the underdog had stayed in contention, making life awkward for Buatsi, who worked behind a protective stance to narrowly win the cleaner periods.
The spectators' acceptance wore thin during constant clinching, with the challenger falling to the floor several times during close exchanges.
The underdog closed well, but multiple periods were challenging to assess. Nevertheless, previous titleholder the boxing analyst - providing analysis for the broadcast network - had it particularly wide for the challenger, scoring for Buatsi just only one stanza.
Buatsi progresses, but with the presence of hard hitter David Benavidez, and Russian champion Dmitry Bivol dominating the weight class, the journey to titles - based on this performance - still appears challenging.
Ricky Hatton Memorial Fuels Manchester Derby Fight
In the secondary fight, Lyndon Arthur defeated Bradley Rea by split-decision in a terrific all-Manchester battle to capture the continental belt.
The stadium fell silent for a extremely emotional memorial prior to the bout as a bell ceremony sounded in remembrance of Manchester's own Ricky Hatton, who succumbed aged 46 in September.
It was the initial significant broadcast boxing event in the city since the passing of Hatton. As the concluding sound disappeared, the silence became a chant of "there's only one Hatton".
The fighting inside the ropes matched the sentiment. Arthur was floored by a significant blow squarely on the face in the early round, standing uncertainly to his footing on the count of eight.
But the traditional red attire of Arthur soon pressed ahead again. From the other corner, the opponent - in opposing blue - was marked up early, significant bruising appearing under his orbital area as the pair exchanged hard punches.
Rea, twenty-seven, delivered effective strikes but Arthur, thirty-four, matched the intensity with effective uppercuts as the action hardly diminished over 12 rounds.
Arthur narrowly won the decision with judges scorecards of even score, 115-113 and 115-112, but each competitor were determined and full of heart, exactly what their inspiration Hatton represented.
