Serrano and Taylor wave to the Madison Square Garden crowd after their fight went down to the wire Saturday. (Sarah Stier/Getty Images)

NEW YORK — “Are you here for the Hulu theater?” the woman asked passersby, in her thick New York City accent, “or da fight?”

Madison Square Garden on Saturday night played host to twin attractions: Franco Escamilla, the comedian, told jokes in the smaller Hulu Theater. Upstairs, in the main building, with the concave ceiling and the championship banners and the 140 years of boxing history, was “da fight.”

The MSG official ended up directing far more people to her left, toward women’s sports history. For the first time ever, two women main-evented a boxing card at the World’s Most Famous Arena, and Katie Taylor and Amanda Serrano put on a show for the announced sellout crowd of 19,187.

Taylor successfully defended her WBA, IBF, WBO and WBC lightweight (135 pounds) titles in a split decision over Serrano, but not before a thrilling finish. Both fighters, correctly sensing the decision would be tight, unleashed a flurry of heavy head shots as the final bell approached, foregoing defense as the crowd reached a fever pitch.

Two judges scored the fight 97-93 and 96-93 for Taylor, and a third 96-94 for Serrano.

“I had to produce a career-defining performance to actually win tonight,” Taylor said afterwards, with a cut over her right eye. “Everyone was talking about coming into this fight, it was the biggest fight in women’s boxing history, but I think it actually exceeded everything that people were talking about.”

That was hardly an easy task, given the heavy promotional campaign spearheaded by Taylor’s representation, Eddie Hearn of Matchroom Sport, and Serrano’s representation, Jake Paul of Most Valuable Promotions.

Paul and his brother, Logan, are a pair of YouTube stars who in recent years have cashed in on their fame inside the boxing ring. Brash, blond and surprisingly competent as boxers, the brothers have pulled in millions for their fights, against other social media stars and former mixed martial arts fighters and boxers (Logan lasted all eight rounds in an exhibition fight against Floyd Mayweather).

The Pauls, depending on the perspective, have either resuscitated boxing, a sport facing decades of decline, or squeezed it for its last drips of profitability. Either way, there’s no denying the renewed interest and bigger paydays for fighters across the board. Serrano and Taylor, who both pulled in seven-figure purses for Saturday’s bout, aired exclusively on DAZN, can both attest to that after years of being underpaid.

The excitement surrounding the event was clear Saturday night as the fighters walked to the ring.

Serrano, who was born in Puerto Rico and grew up in Brooklyn, beamed as her fans sang along in Spanish to her entrance music — “Pepas” by Mau Giemenez Ft. Dj Zeeggo. Taylor, the biggest name in women’s boxing and one of Ireland’s most decorated athletes, was stone-faced as she walked down the aisle. Her fans raised Ireland flags and waved green light sticks.

“Just looking at the packed stadium — unbelievable,” Taylor said later.

The first round was low on histrionics. The fighters were feeling each other out, each landing some notable combinations. Then, Serrano, who holds world championships in seven divisions but is a natural 126-pounder, went on the offensive in the fifth round, busting up Taylor’s nose with a steady stream of powerful blows. At several points in the round, Taylor needed to lean on Serrano to remain upright, and all three judges scored the round for the challenger (10-8, 10-9, 10-9).

Taylor was able to recover, however, and was the clear victor in the final three rounds. With the win over Serrano (42-2-1, 30 KOs), Taylor (21-0, six KOs) remained undefeated in her professional career.

“She’s tough. She’s a warrior. She’s Irish,” Serrano said. “She was able to withstand the power.”

It’s been quite the run for a fighter who was not even legally allowed to box when she began her amateur career. Pretending she was a boy named Kay, Taylor carved her own path and literally blazed the trail for female boxers in her country and abroad.

She faced perhaps her stiffest yet Saturday against Serrano, who looked impressive in defeat. So impressive, in fact, that the boxing world — including Serrano and Paul — is already looking toward a potential rematch.

“We’re going to get the next one,” Paul said, “in Ireland.”

Josh Needelman is the High School Sports Editor at Just Women’s Sports. Follow him on Twitter @JoshNeedelman.