(CNN)Anthony Joshua reclaimed the WBO, IBF and WBA heavyweight titles from Mexican-American Andy Ruiz Jr. in Saudi Arabia's "Clash on the Dunes" on Saturday night.
Britain's Joshua won a unanimous decision from the judges in Diriyah, near Saudi Arabia's capital Riyadh.
He avoided trading big blows with Ruiz the entire fight, instead dancing around the ring and landing jabs and hooks when he found the opportunity.
But with the venue for the promotion heavily criticized by human rights groups, Joshua sported further controversy with remarks he made post-fight, using the term "decapitate" in an interview with American broadcaster DAZN.
"I know that my fans like to see me knock people out and I can do that but sometimes with certain fighters you have to box smarter," said Joshua.
"I understand what Andy brought to the table so I had to decapitate him in a different way."
The build-up to the bout had seen accusations of "sportswashing" -- a practice whereby the staging of high profile sports events is used to improve the reputation of a country with a poor record for human rights.
Diriyah, a UNESCO heritage site, has recently hosted the opening two rounds of the Formula E season, and a big tennis tournament will follow the Joshua-Ruiz rematch.
Pre-fight both Joshua and promoter Eddie Hearn had shrugged off concerns raised by Amnesty International over the issue.
"I just came here for the boxing opportunity. I look around and everyone seems pretty happy and chilled. I've not seen anyone in a negative light out here, everyone seems to be having a good time," Joshua told the BBC.
'Too much partying'
The well-beaten Ruiz admitted he didn't prepare like he should have, enjoying the fruits of his shock victory over Joshua back in June too much before getting down to serious training for the rematch.
"The three months of partying affected me. I should have trained harder. I gained too much weight and I wasn't able to throw my combinations.
"But I don't want to give no excuses. I believe I hurt him a few times but he was boxing his life out." he said.
Saturday's bout was the first for the two heavyweights since Ruiz won a technical knockout during the seventh round in New York in June.
That fight was considered one of the biggest shocks in boxing history, with Ruiz a heavy underdog.
Joshua had been one of three undefeated world heavyweight champion contenders but after his revenge victory can now look forward to a possible unification bout with WBC champion Deontay Wilder, who is set to fight Britain's Tyson Fury in their eagerly-awaited rematch in February.
The New York defeat was the first of Joshua's career, meaning he surrendered all of the WBA (Super), IBF, WBO, and IBO heavyweight titles.
In reclaiming them, Joshua joins boxing greats Floyd Patterson, Muhammad Ali and Lennox Lewis in winning a world heavyweight title back in an immediate direct rematch.
2012 Olympic champion Joshua was improving his career record to 23-1 and handed Ruiz just the second loss of his 35-bout career.