UK light-heavyweight Joshua Buatsi earned a win yet underwhelming debut to life under fresh promotional backing with a points victory over Parker in the Manchester arena.
The Olympic medal winner's activity level likely gained him a majority decision in a competitive ten-round contest at the Manchester venue.
But the challenger had his moments, connecting with powerful clean blows in a fight where the techniques never quite clicked, with constant grabbing marring the action.
The scoring judges scored it 96-94 for to Buatsi, with the final judge a 95-95 draw.
"It wasn't my finest performance but what do champions do? They succeed," Buatsi stated in the ring as he was faced negative reactions from the spectators.
The Londoner returned to winning ways after his first professional defeat - an memorable fight with his previous opponent in February - to claim a twentieth professional win.
Various analysts thought the challenger, thirty-one, merited the decision but the Derbyshire fighter suffered the second setback of his 28-fight career.
Buatsi Claims Triumph in Uneventful Encounter
His career development has stalled in recent times through contract problems and considerable time of lack of fights.
Earlier forecast as the rising talent of the British fight scene, he now is positioned trying to achieve expectations - maybe in what seems like a ultimate opportunity - under new promotional backing.
He opened tentatively, with the two boxers willing to take risks in a tentative opening few rounds.
The challenger, whose sole prior loss came at super-middleweight against his former opponent in 2022 after suffering a hand injury during the bout, was competing in only his second appearance at light heavyweight.
By the halfway stage, the underdog had kept it close, causing problems for the favorite, who operated with a protective stance to narrowly win the more effective stanzas.
The spectators' acceptance diminished amid constant clinching, with the challenger slipping to the canvas several times during close exchanges.
The underdog finished the stronger, but multiple periods were difficult to score. Nevertheless, former world champion Carl Frampton - working with Dazn - had it strongly leaning for Parker, awarding Buatsi just one round.
Buatsi moves on, but with the likes of power puncher Benavidez, and Russian star Bivol leading the category, the path to championship success - based on this performance - still looks steep.
Ricky Hatton Homage Motivates All-Manchester Fight
In the supporting bout, Arthur overcame Bradley Rea by split-decision in a excellent Manchester vs Manchester fight to secure the European light-heavyweight championship.
The venue became quiet for a extremely emotional tribute prior to the bout as ten bells rang in remembrance of the city's native Hatton, who died 46 years old in September.
It was the initial significant broadcast match card in the city since Hatton's death. As the concluding sound ended, the quiet transitioned to a chant of "only one Hatton".
The action inside the ropes equaled the emotion. The eventual winner was knocked down by a significant blow squarely on the chin in the second round, rising shakily to his footing on the referee's count.
But the Manchester United-red attire of Arthur soon pressed ahead again. Across the ring, the opponent - in competitive blue - was damaged soon, significant bruising developing under his face as the fighters landed punishing blows.
The challenger, 27, connected with strong blows but Arthur, thirty-four, responded in kind with effective uppercuts as the pace hardly diminished over the full distance.
The victor narrowly won the result with official scores of draw, 115-113 and 115-112, but each competitor were determined and brave, everything their inspiration the legend represented.
