Heavyweight up-and-comer Jermaine Franklin has tested positive for Covid-19, forcing him out of a meaningful fight with fellow unbeaten American Stephan Shaw, sources with knowledge of the situation told BoxingScene on Sunday.

The 6-foot-2, 235-pound Franklin and 6-4, 240-pound Shaw were due to meet in the 10-round main event of the Ring City USA card on NBC Sports Net on Thursday (9 p.m. ET) at the United States Military Academy at West Point, New York.

Franklin received a positive test and was eventually retested and that one also came back positive for the coronavirus, according to the sources.

Organizers are seeking a late replacement to face Shaw but even if an acceptable opponent is not found on such notice the card will still go ahead as planned, sources said.

Franklin (20-0, 13 KOs), 27, of Saginaw, Michigan, taking on Shaw (14-0, 10 KOs), 28, of St. Louis, was a rare matchup of unbeaten rising American heavyweights both stepping up their level of opposition.

If a new opponent is not found to face Shaw, the co-feature will move up to the main event position. That fight will see WBA women’s featherweight world titlist Jelena Mrjdenovich (41-10-2, 19 KOs), 38, of Edmonton, Canada, defend her belt against southpaw Erika Cruz Hernandez (12-1-0, 3 KOs), 30, of Mexico.

There has also been a change to the opening bout. Junior welterweight Jonathan Navarro (17-0, 9 KOs), 24, of East Los Angeles, who is trained by Robert Garcia, was supposed to end a 17-month layoff and face Juan Pablo Romero (13-0, 9 KOs), 31, of Mexico, in the 10-rounder. However, Navarro has suffered a torn biceps and is out of the fight, a source said. Instead, Romero will face Denier Berrio (22-2-1, 13 KOs), of Colombia, according to a source.

Berrio, who has won two fights in a row, will be fighting in the U.S. for the first time. All of his previous bouts have taken place either in Colombia or Russia.

It’s the second recent fight Navarro has lost out on. Besides having to pull out of Thursday’s bout due to an injury, he had been scheduled to fight Mexico’s Pablo Cesar Cano (33-7-1, 23 KOs) in a 12-rounder on the DAZN undercard of Golden Boy Promotions’ Vergil Ortiz Jr.-Maurice Hooker show on March 20. But that fight was canceled when Cano was forced to withdraw on short notice due to a non-Covid-19 illness.

The card will be the first professional boxing show held at the U.S. Military Academy, which is well known for its amateur program. It will also be the first boxing event held in New York since heavyweight Robert Helenius upset Adam Kownacki in the main event of a Premier Boxing Champions card on March 7, 2020 at Barclays Center in Brooklyn.

Dan Rafael was ESPN.com's senior boxing writer for fifteen years, and covered the sport for five years at USA Today. He was the 2013 BWAA Nat Fleischer Award winner for excellence in boxing journalism.