NEW YORK — It was Carl Frampton’s first fight in New York, a lifelong dream to make it big in the U.S., and he’s well on his way to realizing his goal.

The Irishman engaged in a savage affair Saturday with fellow undefeated champion Leo Santa Cruz and claimed the WBA featherweight title via majority decision (scores of 114-114, 116-112 and 117-111) in a slight upset to establish himself as one of the best pound-for-pound fighters in boxing. USA TODAY Sports scored it 114-114.

With the crowd of 9,062 at Brooklyn’s Barclays Center behind him — they sang along and cheered boisterously throughout — the 122-pound champion weathered Santa Cruz’s punch volume and superior size in a fight of the year candidate on Showtime where both men improved their standing in the sport.

“It’s a dream come true,” said Frampton, who was competing at 126 pounds for the first time. “I had the dream of winning a world title and I won it, but I never thought I’d win in two divisions. It was a tough fight; I wanted it to be a tough fight because I wanted a fight the people could remember. I respect him a lot. He was a true warrior.”

And remember it, they will.

Frampton (23-0, 14 KOs) carried the fight early with movement, defense and cleaner punching. Santa Cruz (32-1-1, 18 KOs) had trouble finding the proper range and was pelted with shots, but never stopped coming forward.

The pro-Frampton audience was whipped into a frenzy with each bomb the “The Jackal” connected on — all 242 of them.

They combined for 160 punches thrown in Round 2 and the pace never let up. Frampton, 29, piled up rounds over the first half and did his best work in the pocket. The biggest damage of the contest was inflicted in that frame when Frampton wobbled the champ into the ropes with a furious flurry.

The Mexico native began to dial in with body shots and slowed the challenger down over the second half with increased volume. They continued to stand toe-to-toe in the middle of the ring and there was nary a clinch. Referee Harvey Dock’s presence went undetected, much to the delight of the raucous Brooklyn fight fans.

“That’s the fight of the year,” said Lou DiBella, who promoted the fight. “It was sensational. Frampton came in here and put on a show. It was like Rock ‘Em Sock ‘Em Robots. It was a classic fight.

“He is the best fighter in the U.K. Period. He’s one of the best fighters in the world pound for pound. I would love to see a rematch.”

Santa Cruz’s father, Jose, worked the corner despite battling cancer since April, but Leo suffered the first loss of his impressive professional career. Though he enjoyed a 2 1/2-inch height advantage and seven inches in reach, Santa Cruz smothered many of his own shots and had trouble matching the smaller man’s speed.

As usual, though, Santa Cruz threw a maniacal number of punches. He once again topped the 1,000-punch plateau, connecting on 255 of 1,002 (25%). Frampton was far less busy but more accurate, landing 242 of 668 (36%).

“It was a tough fight from the beginning,” Santa Cruz, 27, said. “We knew it was going to be a tough fight, but I thought it was close when I’m in there throwing. Maybe the judges were hearing the crowd and thought that every little punch was scoring.

“He has a difficult style, but we know his style and (will) get him in the rematch. The crowd was cheering, and I think the judges saw that. And maybe, without that, we would have had a draw or maybe a decision.”

Santa Cruz, who earned $1 million, certainly has no reason to hang his head. He proved he’s clearly one of the best fighters in the world on the heels of a career-best win in August against Abner Mares. He’s held titles in three weight classes and a return bout with Frampton would be highly anticipated.

This night was about the arrival of Frampton, though, the next U.K. star to announce his arrival stateside. His U.S. debut was inauspicious, a decision over Alejandro Gonzalez in July when the champ was shockingly dropped twice in the opening round.

But Frampton (whose purse was $500,000) rebounded with a victory over Scott Quigg in a massive U.K. fight in February to unify titles at 122 and set up this summer showdown with Santa Cruz (who topped Kiko Martinez on that same night). Frampton also became the first Northern Irish fighter to claim titles in two weight classes with the win.

Neither Frampton nor Santa Cruz had ever faced an opponent like one another before. It’s impossible to tell just how truly great a fighter is until they brush up against someone who meets their equal.

And it’s now clear that Frampton is one of the best pound-for-pound fighters in the world.

“I would love to take this man to Belfast for a rematch and show the people there what a great fighter he is,” he said. … “I want big, memorable fights.”