Conor McGregor said a rematch with Khabib Nurmagomedov was "inevitable" after his knockout win over Donald 'Cowboy' Cerrone at UFC 246.
McGregor made his comeback in style, taking just 40 seconds to stop the American, 36, in Las Vegas, USA.
It was the Irishman's first fight since losing to Nurmagomedov in October 2018.
"That rematch will happen," said McGregor, 31. "Look at the shape I was in in this camp compared with the last. It's non-comparable."
McGregor's defeat by Nurmagomedov was his first UFC bout in almost two years - and his first fight since losing a boxing match to Floyd Mayweather in August 2017.
After McGregor's comeback win, Mayweather hinted on social media that he would come out of retirement for a rematch with the Irishman. However, moments later, the 42-year-old undefeated American posted an image saying "Mayweather Nurmagomedov 2020".
Since beating McGregor, Nurmagomedov remains undefeated. The 31-year-old Russian is scheduled to face Tony Ferguson of the United States on 18 April at UFC 249, although the pair have already had four bouts postponed.
"It's not the be all and end all," added McGregor, who said March was an option for his next fight. "I'll focus on my skills and my training and then carry on.
"The 'who' does not matter, the division does not matter. It's just a case of keeping myself in shape and focused, and I'll take it as it comes. I felt energetic, fresh. I wanted to be in there."
UFC president Dana White believes a rematch between McGregor and Nurmagomedov would be "the biggest fight in the sport's history".
"Conor McGregor looked ridiculous," said White after the Las Vegas bout. "Nobody saw that coming, nobody. I was blown away.
"Going into the Khabib fight, Conor had a lot of personal stuff, some stuff self-inflicted. He had injuries. He has been obsessed with getting that rematch because he knows that he wasn't 100% right.
"With how Khabib won the first fight and how famous he's become, we're looking at [Marvin] Hagler-[Thomas] Hearns, we're looking at [Muhammad] Ali-[George] Foreman, Ali-[Joe] Frazier.
"This is a massive fight with global appeal. It's the fight that you make. It's the fight that makes sense. Khabib versus Conor is the biggest fight in the sport's history."
McGregor was the first UFC fighter to hold titles in two weight divisions simultaneously and his comprehensive win over Cerrone saw him become the first to claim knockouts at featherweight, lightweight and now welterweight.
He struck Cerrone with his shoulder in the clinch before landing a head kick that set up the finish, with McGregor landing a flurry of punches after his opponent dropped to his knees.
"I just went out confident," added McGregor. "When we separated [after the shoulder blow] and I saw the busted nose, I thought: 'Lovely, happy days.'
"I knew Donald was planning to kick me in the head and add to his resume of most head-kick knockouts, so I was happy to land a kick on Donald myself.
"It's such a wild game and a psychological rollercoaster. It's worth every penny this business. It's a good buzz."
Cerrone, nicknamed 'Cowboy', expected McGregor to make a fast start but not to be caught by his shoulder.
"He got me right away and distorted me," said the 51-fight veteran. "I've never seen anything like that. He caught me way off guard.
"He busted my nose, it started bleeding, then he stepped back and head-kicked me. I was like: 'Oh, man, this happened this fast.' I got my ass whipped early."
Nick Peet, MMA journalist on BBC Radio 5 Live
Cerrone looked like he had been hit by a truck. That was exactly what Conor wanted to do.
You could see from the get-go he wanted to get that left hand going, and once Cowboy threw that high kick - which we all agreed was one of his best weapons - he countered with one straight away. That's what led to the finish.
There was no dry ice here tonight, no big emphatic ring walk [as there was against Nurmagomedov]. It was all business. He got in there and got the job done. Now the bravado can come back.
Jorge Masvidal, Kamaru Usman and a few others were pulling their faces cageside. But they're cageside for a reason - they all want the Conor fight. And right now, the power is back in the hands of Conor McGregor. He will now choose what he does next.