British light heavyweight Buatsi secured a victory yet underwhelming start to life under recent management with a decision win over Parker in the Manchester arena.
The Olympic medal winner's punch output appeared to earn him a split decision in a competitive ten-round bout at the Manchester venue.
But the challenger landed significant shots, delivering effective individual punches in a contest where the techniques didn't complement each other, with excessive holding spoiling the contest.
The scoring judges scored it 96-94 for to Buatsi, with the remaining official a 95-95 draw.
"It wasn't my best performance but how do champions respond? They succeed," Buatsi commented in the arena as he was faced boos from the audience.
The Londoner got back to winning after his maiden career setback - an epic battle with his previous opponent in last winter - to earn a twentieth professional win.
Various analysts thought Parker, 31, merited the win but the contender experienced the second defeat of his 28-bout professional journey.
The Champion Claims Win in Dull Match
Buatsi's progress has slowed in the past few years through promotional disputes and considerable time of inactivity.
Previously predicted as the next star of the British fight scene, he now is positioned trying to realize his potential - maybe in what seems like a final roll of the dice - under recent support.
He started carefully, with the two boxers prepared to overcommit in a calculated opening few rounds.
Parker, whose sole prior loss came at super-middleweight against John Ryder in 2022 after breaking his hand during the bout, was competing in only his second appearance at the higher weight class.
By the fight's midpoint, Parker had kept it close, making life awkward for Buatsi, who worked behind a protective stance to barely take the more effective periods.
The audience's tolerance decreased during constant clinching, with the challenger falling to the floor various instances during grappling.
The underdog ended stronger, but several stanzas were hard to judge. Although, previous titleholder the boxing analyst - providing analysis for the broadcast network - had it particularly wide for the challenger, scoring for Buatsi just a single round.
Buatsi progresses, but with the likes of power puncher Benavidez, and Russian champion Bivol ruling the division, the journey to titles - judging by this showing - still seems difficult.
Hatton Tribute Motivates Local Rivalry Battle
In the secondary fight, Lyndon Arthur defeated Rea by divided decision in a terrific all-Manchester battle to win the continental championship.
The stadium became quiet for a extremely emotional homage prior to the bout as 10 bells 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 disappeared, the quiet transitioned to a roar of "there's just one Ricky Hatton".
The action during the bout equaled the sentiment. Arthur was sent to the canvas by a left hook squarely on the chin in the initial stage, getting up unsteadily to his footing on the referee's count.
But the Manchester United-red shorts of Arthur soon pressed ahead again. From the other corner, the opponent - in competitive blue - was damaged quickly, noticeable damage developing under his eye as the pair traded punishing blows.
Rea, twenty-seven, connected with strong blows but the champion, thirty-four, responded in kind with stinging uppercuts as the action seldom decreased over twelve rounds.
Arthur barely secured the decision with scoring tallies of even score, 115-113 and wider gap, but each competitor were persistent and full of heart, everything their hero the legend represented.
