By Keith Idec

It would provide promoters with a saleable storyline, but Adam Kownacki won’t step in for Jarrell Miller to challenge Anthony Joshua.

The unbeaten Polish heavyweight contender is Miller’s close friend and definitely would help sell the remaining 6,000 or so tickets for Joshua’s U.S. debut on June 1 at Madison Square Garden. Based on how Kownacki and Miller typically assess their regular, spirited sparring sessions, the Brooklyn-bred Kownacki also would have at least as good a chance to upset Joshua as Miller.

Kownacki (19-0, 15 KOs) was toward the top of promoter Eddie Hearn’s list of potential replacements for Miller once a New York State Athletic Commission spokesperson confirmed Wednesday that Miller’s license application has been denied for his fight against Joshua because Miller failed a performance-enhancing drug test last month. When BoxingScene.com reached out to Kownacki’s manager, however, Keith Connolly revealed that Kownacki has already signed a contract a fight on one of Al Haymon’s Premier Boxing Champions shows on an unspecified date this summer, probably at Barclays Center in Brooklyn.

Connolly declined to discuss Kownacki’s upcoming opponent, but he made it clear Kownacki would be willing to fight Joshua at some point in the future. The 30-year-old Kownacki would’ve had just six weeks to prepare to challenge Joshua for the British superstar’s IBF, IBO, WBA and WBO titles.

“The rumors of Adam Kownacki fighting Anthony Joshua on June 1st are not true,” Connolly told BoxingScene.com. “Al Haymon and I have made a deal for a fight sometime this summer for Adam to fight on PBC, in New York, where he has a huge fan base. Details of the fight will be released over the next couple weeks.”

Kownacki’s next fight will be broadcast either by FOX or Showtime. Joshua’s fight on June 1 will be streamed by DAZN in the United States.

Speculation persists regarding Kownacki eventually challenging WBC heavyweight champ Deontay Wilder. Connolly declined to discuss the possibility of a Wilder-Kownacki bout, but he acknowledged that Kownacki would be open to boxing Joshua if given an appropriate amount of time to train.

“Anthony Joshua is a great fighter and a great guy,” Connolly said. “It is a fight that somewhere in the future would be a huge fight for the New York fans. The fight is definitely something that can be made down the road, since I have close relationships with Al Haymon and Eddie Hearn. The fight will definitely happen. It just won’t happen June 1st.”

Meanwhile, Hearn still seeks a suitable substitute for Miller (23-0-1, 20 KOs), whose rivalry with Joshua (22-0, 21 KOs) had helped sell a fight Joshua was heavily favored to win.

Kubrat Pulev (27-1, 14 KOs), the mandatory challenger for Joshua’s IBF title, and WBA “world” champ Manuel Charr (31-4, 17 KOs) also have been eliminated from contention to step in for Miller.

Bulgaria’s Pulev suffered a cut above his left eye during a seventh-round knockout victory over Romania’s Bogdan Dinu (18-2, 14 KOs) on March 23 in Costa Mesa, California. The California State Athletic Commission also has suspended Pulev’s license due to the controversy caused by Pulev kissing Vegas Sports Daily’s Jennifer Ravalo during a post-fight interview that night.

Germany’s Charr has not been tested recently by the Voluntary Anti-Doping Association, a requirement for facing Joshua on June 1. Miller failed a urine test administered by VADA on March 20.

The trash-talking contender from Brooklyn tested positive for GW 501516, also known as endurobol, a banned substance that can burn off excess fat, speed up recovery while training and significantly enhance endurance.

With Kownacki, Pulev and Charr out of the mix, Hearn could extend offers to Luis Ortiz or Michael Hunter, who recently signed a multi-fight contract with DAZN. Hearn has mentioned Dillian Whyte (25-1, 18 KOs) as a potential replacement for Miller, but a Joshua-Whyte rematch would be a huge stadium fight in England and thus is unlikely for June 1 in New York.

Las Vegas’ Hunter (16-1, 11 KOs) is ranked No. 10 by the IBF and No. 12 by the WBA. Hunter has lost only to Oleksandr Usyk (16-0, 12 KOs), the former undisputed cruiserweight champion who beat Hunter by unanimous decision in a 12-rounder two years ago at MGM National Harbor in Oxon Hill, Maryland.

Multiple sources have informed BoxingScene.com that Ortiz is interested in replacing Miller. It isn’t clear, however, whether Haymon could compensate the Cuban contender with a comparable purse for a fight later this year to keep Ortiz (31-1, 26 KOs, 2 NC) from pushing for the Joshua fight.

A rematch with Wilder, assuming Wilder defeats Dominic Breazeale on May 18 at Barclays Center, seemingly would be the only such fight Haymon could offer Ortiz.

Keith Idec is a senior writer/columnist for BoxingScene.com. He can be reached on Twitter @Idecboxing.