Anthony Joshua returned to winning ways with a unanimous points victory over Jermaine Franklin at London's O2 Arena.
The British heavyweight, 33, controlled the contest against the durable American but it was not the explosive early finish many expected.
Two judges scored it 117-111 and one 118-111 to Joshua.
Tempers flared after the final bell as the two fighters squared up to each other, prompting their teams to enter the ring and be separated by security.
It is Joshua's first win in more than two years, having consecutive bouts to WBA (Super), IBF and WBO world champion Oleksandr Usyk.
"No knockout, so no good. It is a brutal sport, but knockouts are everything. I'm not too happy," Joshua told 5 Live Boxing.
"I could have thrown more shots, and I should have, no excuses. But I will. That is part of coming back; you have to be your own biggest critic."
He also called out fellow Briton and WBC champion Tyson Fury, saying: "I try and provide for the fans. I know who they want. They said Tyson Fury - the ball is in his court."
Joshua has now won 25 fights, with 22 stoppages, and lost three since turning professional in 2013.
It is a second defeat for Franklin, 29, having lost to Briton Dilian Whyte in November.
No vintage 'AJ' as tempers flare
Joshua returned to the O2 Arena - once a fortress for the Watford fighter - after seven years. His seven previous fights at the venue ended inside the distance, but this was not vintage Joshua.
A boisterous sellout crowd, including popstar Liam Payne and journalist Louis Theroux, were in attendance, eager to see whether Joshua - still one of the biggest names in British boxing - remained a force in the division.
Away fighter Franklin - who earlier travelled on the London underground to the arena due to traffic - entered the ring first to huge jeers. Joshua followed, marching to the ring with a look of determination.
Joshua started strongly, taking the centre of the ring and doubling up on the jab to pierce Franklin's guard, with quick feet to stay out of range of any advances. A thudding straight right got Franklin's attention at the start of the second.
The Michigan fighter - who shed 23lbs since losing to Whyte - came out strong in the third, growing in confidence and showing he was not there to make up the numbers.
Joshua landed a telegraphed uppercut from range in the fourth and both men found success in the fifth.
Boxing fans and pundits felt Joshua needed to win in style against a fringe world-level contender. Even 'AJ' himself said he needed to make a statement, but it was starting to look as if that would not be the case.
Franklin began to tire into the second half of the fight, Joshua landing a sharp hook on the inside. The two men stood their ground and exchanged glares after the bell in the seventh.
But when the AJ of old would have pushed for a knockout, the fight instead became scrappy as both men were warned for holding in the ninth.
Joshua enjoyed more success in the following round, stunning Franklin with a terrific uppercut. He grinned and, perhaps for the first time in the fight, the former unified heavyweight champion was reminiscent of his old self.
A complacent Joshua was reminded of the danger Franklin poses, taking a couple of clean shots, but out-jabbed his opponent, who continued to clinch, in the final rounds.
In scenes not too dissimilar to his outburst when he lost to Ukrainian Usyk in August, Joshua once again allowed his frustration to get the better of him after the final bell.
He tapped Franklin on the back of the head, who reacted and then AJ decided to wrestle with his opponent before Franklin's corner got involved. The melee continued outside the ring, pushing back the barriers separating the teams from the media.
"Last time I grabbed the mic, it was a bit chaotic," Joshua said afterwards. "I'm calm - I appreciate everyone coming out this evening.
"Inside the ring, it is a different energy so I apologise to those watching."
Is Fury next?
Fans wanted to see the return of the old Joshua. The ferocious, ruthless combination puncher who stopped his first 20 opponents inside the distance.
But the last time Joshua won in the first half of a fight was in 2016, against Eric Molina. Perhaps that is a testament to the level of opponents he has faced since then.
Franklin - a fringe world-level contender - gave Joshua a harder night's work than most expected. Nevertheless, the pressure was on. A defeat for Joshua would have been difficult to come back from.
Despite an underwhelming performance, Joshua is keen on a match-up with Fury.
"I would be honoured to fight for the WBC heavyweight championship of the world," Joshua said.
"If he's listening, he knows my promoter, we've had dialogue before, so let's continue this. We ain't getting any younger."
Promoter Hearn added: "There may be an opportunity to do the Tyson Fury fight next.
"If it is there, it'll be difficult for AJ not to take it. He may think he will never get it.
"The sensible thing is to have another fight with Derrick James to improve; Dillian Whyte is a great option. The first fight was epic. It is all about timing. Money? Not so much, but he is looking at big fights.
"That was his career on the line and he was apprehensive for that reason."
Unbeaten Fury's last outing was a trilogy bout win over Derek Chisora in December. The Morecambe fighter will be looking for a high-profile opponent for his next fight.
Joshua-Fury is arguably the most lucrative bout for both men. In terms of appeasing boxing fans, it would go a little way in clawing back some credibility for the sport after an undisputed fight between Fury and Usyk fell through.
