NEW YORK — Katie Taylor and Amanda Serrano will complete their historic trilogy later Friday night when they collide at Madison Square Garden in New York City.

Before that, however, there's an stacked undercard for boxing fans to sink their teeth in.

Alycia Baumgardner, Chantelle Cameron, Savannah Marshall and Ellie Scotney will all be in action.

London’s Ellie Scotney kept her unbeaten record and her IBF, WBO and Ring magazine titles intact in junior featherweight action as she outboxed Yamileth Mercado and took the Chihuahua native’s WBC belt in the opener of the four-fight main card.

Mercado (24-4, 5 KOs) found out early that Scotney’s speed was going to be an issue, but with the Brit not possessing fight-changing power, the Mexican tried wild aggression to get the better of her opponent. Her wide and wild shots didn’t serve her well, though, as Scotney (10-0) either stepped out of range or countered with little effort.

In the fifth, Mercado’s increasing frustration was evident. Scotney went back to her corner with a cut over her left eye, but it was Mercado who ended the frame with her own cut to deal with as she had to be wondering what she needed to do to get into the fight.

Those answers never came, and while the bout went the distance, the final scores of 100-90 and 98-92 (twice) were never in doubt.

Australia’s Cherneka Johnson arrived with the WBA bantamweight title, and after an impressive stoppage of Shurretta Metcalf she left the Madison Square Garden ring with her IBF belt and the vacant WBC and WBO belts, too.

The end came when referee Charlie Fitch halted the bout two seconds into the ninth round.

Johnson’s steady pressure baffled Metcalf immediately, and the difference in technique between the two was evident. Metcalf, who was dropped in the fourth round and rocked on a number of occasions, didn’t have her legs under her throughout the bout, which led to her return fire having no effect on the soon-to-be undisputed champion at 118 pounds.

In response, Fitch and the ringside physician kept their eyes closely on the action until finally stopping the fight in spite of Metcalf’s protests.

Chantelle Cameron kept her hopes for a rubber match with Katie Taylor alive as she scored a clear-cut 10-round unanimous decision over Jessica Camara in defense of her interim WBC junior welterweight title.

Scores were 99-91, 98-92, 99-91 for Northampton’s Cameron.

Montreal’s Camara (14-4-1, 3 KOs) took the fight to Cameron (21-1, 8 KOs) at the start and she refused to back down from any exchanges with the Brit. The unfortunate part for the Canadian was that Cameron was more than willing to brawl at close range, and what resulted was compelling — but one-sided — action throughout.

The crisper punches continued coming from Cameron, and the pace of the fight began to take its toll on Camara, whose face showed the wear of battle. After the seventh round, Camara was on wobbly legs as she returned to the corner, prompting a visit from the ringside physician. Camara was cleared to continue,and she gamely fought on, but it was all Cameron down the stretch

Junior featherweight contender Ramla Ali survived a spirited effort from Brazil’s Lila Furtado before emerging victorious via unanimous decision.

Scores in the eight-rounder were 77-75 twice and 78-74 for Somalia’s Ali.

Furtado (11-3, 2 KOs) came out firing from the opening bell, swarming Ali (10-2) throughout the bout. After taking some time to get acclimated to the pace, Ali began landing good counters on the inside, nearly dropping Furtado in the second round. That was as close as the fight came to producing a knockdown, and Ali’s cleaner shots likely made a positive impression on the judges, even if the crowd didn’t agree with the decision.

In the opener at Madison Square Garden, two-time Canadian Olympian Tamm Thibeault put herself in line for a shot at the vacant WBA middleweight title with a fifth-round TKO win over previously unbeaten Pittsburgh native Mary Casamassa.

The WBA final eliminator was scheduled for eight three-minute rounds.

In control from the start, Quebec’s Thibeault dropped her foe in the opening round, and while Casamassa was game she was outgunned. The 2020 and '24 Olympian picked up the pace in the fourth, and it was a matter of time until the end came at 2:18 of Round 5, with referee Charlie Fitch stepping in after an unanswered barrage of punches from Thibeault.

Thibeault moves to 3-0 with 2 KOs. Casamassa falls to 6-1 with 1 KO.