Amanda Serrano turned a pound-for-pound showdown into yet another showcase performance.

The record-setting seven-division champion turned in a masterclass performance in scoring a 9th round knockout of Daniela Bermudez. A left hook, right hook combination put Argentina’s Bermudez down for the ten count at 1:33 of round nine in their WBC/WBO/IBF featherweight title fight Thursday evening at Plaza del Quinto Centenario in Old San Juan, Puerto Rico.

Serrano was fighting on her home island for the first time in nearly four years but made it well worth the wait. The 32-year old southpaw last appeared in Puerto Rico in a July 2017 repeat knockout win over Edina Kiss, having already established herself as a five-division titlist by that point. Title wins at junior bantamweight and junior welterweight have since followed, along with her second tour as a featherweight following a dominant 10-round unanimous decision win over Heather Hardy in Sept. 2019.

Getting her back on a high-profile stage has proven challenging, including the debacle in attempting to piece together a superfight with unbeaten World lightweight champion Katie Taylor. The journey ultimately led Serrano to a pound-for-pound showdown with Bermudez, who hadn’t lost in nearly seven years while in pursuit of a title in her fourth weight division.

Bermudez boxed from the outside in the opening round, while Serrano was consistently first to the punch while connecting with her jab and straight left hand. The action wasn’t entirely one way, as Bermudez was able to connect with a few right hands which Serrano took well while continuing to score with her potent left.

Serrano continued to take the lead in round two, though well aware every step of the way that she was in a fight. Bermudez continued to find a home for her right hand, even if not landing enough to win the rounds.

Bermudez switched to southpaw during several points in round three, looking to target the body. Serrano adjusted to the tactic, shooting her jab but also having to fight off of the ropes as Bermudez continued to come forward.

Round four was spent at close quarters, with Serrano getting the better of the exchanges on the inside. Bermudez sought to impose her will but left herself open for right hooks to the body by Serrano, whose infighting skills served her well. Serrano ended the round slipping a right hand along the ropes and coming right back with a straight left.

Serrano returned the action to her preferred pace in round five. The unified champ allowed Bermudez to walk straight forward, picking her apart with combinations. Serrano connected with a straight left to the body late in round six which appeared to knock the wind out of Bermudez.

The closest to having to deal with adversity for Serrano came after round seven, when she returned to a corner which was one person short. Jordan Maldonado, Serrano’s head trainer/manager/brother-in-law was escorted away from ringside for being overly critical of referee Roberto Ramirez Jr. Serrano didn’t let it affect her, in fact turning in her best round of the fight to that point as she picked apart Bermudez while keeping action in the center of the ring.

“I didn’t let it bother me,” insisted Serrano. “I have a great team. I have Gary Stark Sr. who works with Jordan. I have the best team. I still heard (Jordan), it didn’t matter.”

The manner in which Serrano closed the show certainly qualifies that remark.

Bermudez was game throughout, however also outgunned as the fight entered round nine. Serrano picked up on that, wearing down her pound-for-pound rival with crisp body shots. A left hand and right hook downstairs was enough to force Bermudez to turn away in pain, causing a delayed reaction knockdown. Bermudez remained on the canvas for the full ten count, thus ending her ultimately failed bid in seeking a fourth divisional title.

Bermudez falls to 29-4-3 (10KOs) with the defeat, ending a seven-year unbeaten streak. She still remains the IBF junior featherweight titlist, after having won belts at junior bantamweight and bantamweight.

Serrano storms to 40-1-1 (30KOs), having won 26 fights in a row dating back to 2012. The win marks the first defense of her unified WBC/WBO title reign, while adding the vacant IBO title in the process.

“When I saw the body shot—my coach Gary told me, two hooks to the body and that’s what happened,” noted Serrano, who led 80-72 on all three scorecards at the time of the stoppage. “We knew she was tough. She’s Latina, she’s from Argentina. We know that Argentine fighters are tough and she was ready. I beat her to the body. Maybe I have to change my name to “Body Snatcher.”

Meanwhile, her goal remains intact of becoming the featherweight belt collector.

Plans for this night initially began as a discussed unification bout with long-reigning Jelena Mrdjenovich (41-10-2, 19KOs) for what would have been a WBC/WBA/WBO/IBO title unification clash. Edmonton’s Mrdjenovich served as the longtime WBC belt—having held the title since regaining it in a win over Melissa Hernandez in their May 2013 rematch—while Serrano was the interim titlist along with holding the WBO crown.

Talks were abandoned after it was determined that Mrdjenovich was not able to honor the proposed fight date in time, although specifics remain disputed by the 38-year old. Neverthless, Serrano was elevated to full champ and Mrdjenovich was named “Champion in Recess” by the WBC, while still holding the WBA featherweight title.

Also on the title stage is Denmark’s Sarah Mahfoud (10-0, 3KOs) who claimed the IBF belt in her most recent win last February in Copenhagen.

After having spent her entire career moving up and down in weight while creating her own history, Serrano is determined to stay put long enough to provide Puerto Rico with something it has never enjoyed in the four-belt era (five, counting the IBO)—someone who has held them all at once.

"I want to become undisputed featherweight champion,” vows Serrano. “I want to be the first champion to become undisputed to come from Puerto Rico.

“Nothing against any champ; I want those belts. If they want these belts they have to come through me."

The bout served as the main event of NBC Sports Network’s Ring City USA series.

Jake Donovan is a senior writer for BoxingScene.com. Twitter: @JakeNDaBox