Anthony Joshua disputed claims made by Joseph Parker's team that Italian referee Giuseppe Quartarone was unable to communicate effectively with the fighters during Saturday's heavyweight unification clash in Cardiff.

Joshua added Parker's WBO crown to his WBA and IBF titles after being forced to go the 12-round distance for the first time in 21 professional fights.

Verdicts of 118-110 (twice) and 109-109 reflected the 28-year-old's superiority over the course of a contest that will not live long in the memory.

The prospects of the cagey affair catching fire were compromised by Quartarone's over-zealous interference on many of the occasions the fighters tried to exchange at close quarters.

Getting the better of Joshua on the inside was presumed to be a possible route to victory for Parker and, although the New Zealander was keen to credit Joshua, it was not one he had the chance to explore fully.

"The bigger and better man won on the day," he said, after suffering a maiden loss in his 25th career outing. "We've got a lot to work on.

"I fared away from using my double jab to set up the punches I wanted to throw. Everything is learning and you have to come back stronger."

Asked about Quartarone's role in the fight, Parker replied. "When the ref came to the dressing room he couldn't really speak English. Kevin [Barry, Parker's coach] was trying to speak to him and ask questions about how he wanted to control the fight.

"We're not blaming the ref but, when we got on the inside and tried to work... I wanted to work on the inside more."

Barry went on to question the British Boxing Board of Control for approving Quartarone's appointment but Joshua painted an entirely different picture when he emerged later for the pre-fight news conference, flanked by a gleaming and growing collection of belts.

"The communication was all in English," he said. "He spoke to us before in the changing room and there was no translator – all in English."

Joshua's promoter Eddie Hearn added: "I'd like to clear up that comment from Kevin Barry's team that the referee didn't speak English.

"The entire talk in the changing room for about two minutes for the rules was in absolutely perfect English."

Moving as sharply behind the microphone as he had in the ring earlier, an amused Joshua saw a chance to make mischief.

"If you check my website soon there'll be a little behind-the-scenes clip and now we'll probably put in that bit with the ref speaking English," he added.

"I think it's hard to please everyone. His first language isn't English but he does speak it and he is fluent. Maybe he hasn't got a cockney accent but he can definitely speak English."

One area where there was is no danger of anything being lost in communication is which opponent Joshua wants to face next – outspoken WBC champions Deontay Wilder, in order to complete the set of the heavyweight division's major belts.

"Yes, that's correct. I think 2018 was always the time to capture all the belts and we're one away now," Joshua added, before challenging Wilder to bring his promotional bluster to the negotiating table.

"I'm not into that business of hype, hype, hype and talk, talk, talk, A lot of negotiations can go on over social media and YouTube channels but business negotiations have to take place in confidential privacy.

"That's when you see how serious people are about taking fights."