British light-heavyweight Joshua Buatsi made a winning yet disappointing beginning to his career under recent management with a points victory over Parker in the Manchester arena.
The Olympic bronze medallist's work rate seemingly secured him a majority decision in a close 10-round contest at the Manchester venue.
But the challenger had his moments, connecting with powerful clean blows in a fight where the techniques didn't complement each other, with frequent clinching marring the fight.
Two judges had it 96-94 in favor to Buatsi, with the third a 95-95.
"It wasn't my best performance but how do champions respond? They prevail," Buatsi said in the ring as he was met by disapproval from the spectators.
The British fighter bounced back after his first professional defeat - an thrilling contest with Callum Smith in February - to secure a twentieth professional win.
Several boxing experts thought the challenger, thirty-one, should have been awarded the victory but the Derbyshire fighter suffered the second loss of his 28-bout professional journey.
The Champion Claims Victory in Uneventful Match
His career development has slowed in recent times through contract problems and extended periods of inactivity.
Previously predicted as the next star of the British fight scene, he now finds himself trying to achieve expectations - maybe in what seems like a last chance - under recent support.
He started carefully, with both competitors willing to take risks in a calculated early stages.
The challenger, whose only previous defeat came at super-middleweight against his former opponent in 2022 after damaging his hand in the contest, was making just his second appearance at light-heavyweight.
By the fight's midpoint, the underdog had kept it close, creating difficulties for the favorite, who operated with a solid defense to edge the better rounds.
The crowd's patience decreased during frequent holding, with Parker falling to the floor multiple occasions during close exchanges.
The underdog finished the stronger, but several stanzas were challenging to assess. However, ex-champion the boxing analyst - providing analysis for the broadcast network - had it particularly wide for Parker, giving Buatsi just only one stanza.
The victor progresses, but with the caliber of heavy hitter David Benavidez, and Russian champion Bivol leading the category, the road to world glory - on this evidence - still seems difficult.
Hatton Tribute Fuels Local Rivalry Contest
In the supporting bout, Lyndon Arthur beat Bradley Rea by split-decision in a terrific local rivalry battle to secure the European light heavyweight belt.
The venue became quiet for a deeply poignant homage ahead of the contest as 10 bells rang in honor of the city's native Ricky Hatton, who died aged 46 in recently.
It was the initial significant broadcast match card in the city since Hatton's passing. As the final chime faded, the silence transitioned to a shout of "there's just one Ricky Hatton".
The fighting within the ring equaled the feeling. The eventual winner was knocked down by a significant blow flush on the jaw in the initial stage, getting up unsteadily to his footing on the count of eight.
But the traditional red shorts of Arthur soon came forward again. Across the ring, the opponent - in rival City blue - was injured quickly, heavy swelling appearing under his orbital area as the pair traded hard punches.
The challenger, twenty-seven, delivered effective strikes but Arthur, 34, matched the intensity with powerful upward punches as the action hardly diminished over the full distance.
The victor barely secured the result with judges scorecards of 114-114, close margin and wider gap, but both fighters were relentless and brave, exactly what their idol the legend embodied.
