Heavyweight Dillian Whyte laboured to a majority points victory against American Jermaine Franklin in London.
Whyte, 34, almost stopped Franklin in the final seconds after 12 mostly stale, uneventful rounds.
Two judges gave Whyte the nod with cards of 116-112, while the third saw it as a 115-115 draw.
Anthony Joshua was watching ringside as eyes turn to a potential rematch between the British old rivals in the new year.
As Whyte exchanged a few cordial words with Joshua at ringside, Franklin expressed discontent with the scorecards and called for a rematch.
"I felt like I got robbed on the decision, I felt like a did enough," the 29-year-old said.
Whyte was fighting under the tutelage of his new trainer Buddy McGirt for the first time and admitted he was "fighting to a new set of instructions", revealing his corner told him to stay behind his jab.
"An undefeated heavyweight's the hardest thing to beat on this planet," Whyte said.Parker forced to retire in Ryder fire fightBriton Hughes claims WBA world title in just fifth pro fight
"He's undefeated and he's got a lot of beans in his body. His stock rose tonight.
"I could've probably been a bit more active and let off a few more big shots."
Whyte's comeback falls flat
Whyte had 19 knockouts on his record before his encounter with Franklin and there were high hopes of an explosive return inside the OVO Arena in Wembley.
The Jamaica-born fighter was in action for the first time since being stopped by WBC champion Tyson Fury at Wembley Stadium in April.
But Whyte set the tone for a slow-paced fight from the first bell, preferring to feel out Franklin rather than push for early success.
It was the American who was throwing most of the punches and he did some minor damage to Whyte in the third with a quick right and left-hand combination.
Franklin landed another long right in the fourth, with hardly anything of note coming back from Whyte.
Just as it seemed a snail's pace had been established, Whyte fired off a flurry of hits in a welcome expression of intent. But the moment was fleeting.
The fifth round, and the entire fight in truth, followed the same pattern.
Whyte would momentarily inject some fire into the fight, pushing Franklin back, only to take his foot off the gas.
After an opening of no meaningful exchanges, Franklin invited Whyte onto him. The crowd, now mostly conversing among themselves, tried to urge both fighters on.
Whyte was then tagged by a right hand from Franklin, but again seemed unconcerned by any power his opponent might possess.Anthony Joshua, who beat Whyte in 2015, was ringside
He just smirked at Franklin and slowed down again.
The crowd's encouragement fell on deaf ears as Whyte thought he was ahead on the scorecards and appeared content to stroll to the final bell.
Whatever plan he was trying to execute, it almost paid off in the final seconds of the 10th round as he landed a big right on Franklin.
The American shuddered, but did not go down. Hopes rose in the arena for a late knockout, but they were quickly dashed as Whyte and Franklin settled back into their previous rhythm for the final two rounds.
Whyte, however, did finish the fight on the front foot, hurting Franklin by landing his first clean left hand.
His previously undefeated opponent stumbled backwards into the ropes, but the bell rescued Franklin.
It was a strange performance from Whyte, who has built a career on his crowd-pleasing fights and explosive nature inside and outside the ring.
But with Joshua watching on and their rematch some seven years in the making, perhaps Whyte will feel he has done his chances of convincing his long-term nemesis to face him again no harm.
Wardley survives firefight against GormanWardley has 14 knockouts from 15 wins
Fabio Wardley claimed the British heavyweight title after coming through a gruelling encounter with Nathan Gorman.
Gorman started brightly and broke Wardley's nose in the second round. Blood began to pour from Wardley's visibly shattered nose and Gorman tried to move in to finish the fight.
But the injury sparked a ferocious response from Wardley, who started stepped forward and began landing on a stunned Gorman.
He put Gorman down with a flurry of right hands and stood over his opponent, roaring down in his direction.
Gorman was down again moments later but the bell arrived to save the 26-year-old.
It proved a short reprieve, as Gorman was caught by a huge right hand in the third and collapsed against the ropes.
He climbed back to his feet again, but with Wardley piling on the pressure, Gorman's corner saved him from further damage by throwing in the towel.
"That was a really exciting heavyweight performance from Fabio Wardley," promoter Eddie Hearn said of his fighter.
Wardley is now undefeated in 15 outings with 14 knockouts.
"Twenty twenty three is the year of Fabio Wardley. It's the year I really kick on," the 27-year-old said.