Bantamweight contender Joshua Greer Jr. will take on former world title challenger Antonio Nieves in his next fight.

Top Rank on Tuesday announced Greer-Nieves as the co-feature for the Top Rank Boxing on ESPN+ show headlined by the Shakur Stevenson-Joet Gonzalez vacant featherweight world title fight on Oct. 26 (ESPN+, main card at 10 p.m. ET with preliminaries beginning at 6:30 p.m. ET) at the Reno-Sparks Convention Center in Reno, Nevada.

Top Rank also made the rest of the undercard official. It will include junior lightweight Mikaela Mayer, Stevenson’s teammate on the 2016 U.S. Olympic team. She will defend her regional belt against Alejandra Zamora in a 10-round bout.

“Joshua and Mikaela are two of the most charismatic young fighters in boxing,” Top Rank chairman Bob Arum said. “Having them on the card in tough fights, along with a great championship bout in Stevenson-Gonzalez, is a bonus for Reno fight fans and everyone watching on ESPN+.”

Greer (21-1-1, 12 KOs), 25, of Chicago, who will defend his regional belt in a 10-round fight against Nieves, is coming off a controversial 12-round decision against Nikolai Potapov on July 13.

“I want to show everyone on Oct. 26 what I’ve been working on,” Greer said. “I’m only getting better. Every fight is a learning experience, and I am going to show Antonio Nieves what I’m about. The knockout didn’t come in my last fight, but it’s all part of the game. I’m bringing back the pillow, and after I beat Nieves, I will be Mr. ESPN+.”

Before each fight, Greer has a custom pillow made, which he unveils after knocking out his opponent.

Nieves (19-2-2, 11 KOs), 32, of Cleveland, Ohio, has won two fights in a row since suffering back-to-back losses — a 10-round split decision to Potapov and a sixth-round knockout when he challenged Japanese pound-for-pound star Naoya Inoue for a junior bantamweight world title in September 2017.

“My primary goal is to become a world champion,” Nieves said. “Joshua Greer Jr. is ranked second by one of the major sanctioning organizations and third by another. I am coming to Reno to beat him, take over his sport in the rankings and win a world championship in 2020.”

Mayer (11-0, 4 KOs), 29, of Los Angeles, is coming off a lopsided 10-round decision against Lizbeth Crespo on June 15 on the Tyson Fury-Tom Schwarz undercard in Las Vegas.

“It’s been a great eight-week camp for this fight, and everything is coming together,” Mayer said. “There’s been talk about my fighting style, and a lot of people have been impressed with how I’ve been working the body. Others want to see me box more on the outside. Nobody’s wrong, but this is just the process of becoming a well-rounded pro. I want to be great on the inside and the outside and that requires working both ways during my fights.

“I’m ready to put it all together, get this win Oct. 26 and then get my title shot. It’s very cool to be the co-feature on the card of my Olympic teammate, Shakur Stevenson.”

In other undercard fights that will stream on ESPN+:

  • Lightweight Albert Bell (15-0, 5 KOs), of Toledo, Ohio, who is coming off a career-best 10-round decision win over then-unbeaten Andy Vences on June 15, will return against Philadelphia’s Frank De Alba (23-4-2, 9 KOs) in an eight- or 10-rounder.

  • Vences (22-1-1, 12 KOs) of San Jose, California, will look to bounce back from the loss to Bell against the Philippines’ Mark Bernaldez (19-2, 13 KOs) in an eight- or 10-round fight.

  • Albuquerque, New Mexico, featherweight Jason Sanchez (14-1, 7 KOs) will take on former world title challenger Adeilson Dos Santos (19-6, 15 KOs), of Brazil, in an eight- or 10-round bout. Sanchez will be fighting for the first time since losing a unanimous decision to Oscar Valdez, whom he challenged for a featherweight world title on June 8 in Reno.

  • Junior lightweight Tyler McCreary (16-0-1, 7 KOs), of Toledo, Ohio, will fight Pittsburgh’s Matt Conway (17-0, 7 KOs) in an eight-rounder.

  • A pair of former U.S. amateur standouts will make their long-awaited professional debuts in four-rounders. Welterweight Xander Zayas, 17, of Plantation, Florida, who was 16 when he became the youngest fighter to ever sign with Top Rank in its 53-year history in March, will face an opponent to be named. Toledo, Ohio, heavyweight Jared Anderson, a two-time U.S. national champion, who signed with Top Rank last month, will face Daniel Infante (1-2, 0 KOs) of Youngstown, Ohio.

  • Reno junior welterweight JJ Mariano (1-0, 1 KO) will face Trinity Lopez (1-0, 0 KOs) in a four-round bout. Mariano will be returning to the arena where he scored a knockout June 8 on the Valdez-Sanchez card.

  • Lightweight Diego Elizondo (2-0-2, 0 KOs), from nearby Carson City, Nevada, will fight Port Arthur, Texas, product Jose Ceja (1-4-2, 0 KOs) in a four-rounder.