Joshua Buatsi restored his hopes of a light-heavyweight world title shot in controversial circumstances as he secured victory over Zach Parker at Manchester's Co-op Live.
The former WBO interim champion took a close 96-94, 96-94 and 95-95 majority decision over his opponent to bounce back from a first career loss against Callum Smith.
Yet for long portions of the fight, Buatsi appeared to be outboxed by Parker, the former British super-middleweight champion bidding to build his own case for a major strap.
Having entered the contest as the underdog, the Derbyshire fighter built from a bright start and looked to have done enough to claim a comfortable margin on the scorecards.
Instead, he suffers a second career loss against an opponent who frequently looked a shadow of his former self, with the judges' decision met by boos around the venue.
Buatsi now moves into prime position to face the winner of David Benavidez and Anthony Yarde's WBC light-heavyweight title bout, which takes place in Riyadh this month.
Following a stacked undercard littered with contenders and pretenders to the division's domestic throne, both men arrived to an arena baying for a statement performance.
Parker offered the more disciplined start of the pair across the first two rounds, with a neat left hook in the first followed by some clever work with the uppercut in the second.
Buatsi's astute ring IQ helped him hold his position across the third, but the Rio 2016 favourite seemed to suffer in comparison through the fourth with a lacklustre workrate.
At the halfway stage, seemingly down on the cards, the star spent the fifth round trying to stalk his foe down, only to find himself outboxed around the outside in the sixth.
Parker frequently cut down any head of steam with a clinch or his own counter-blows, frequently frustrating his rival's corner and continuing to work off the jab in the seventh.
Exchanges across the eighth and ninth saw the former slow somewhat, but with frequent interventions needed to split the pair apart, Buatsi still could not find an opening.
A hard right leading into the tenth followed by some clever body work helped the latter finish on a high - and ultimatley, it proved to be enough for the judges to deliver a shock.
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