The heavyweight fight everyone wants to see -- Deontay Wilder vs. Anthony Joshua -- could happen in the next 6 months ... says the man in charge of broadcasting the event.
TMZ Sports spoke to Stephen Espinoza -- Showtime's president of sports and event programming -- who tell us the "ball is rolling" on making the fight happen in 2018.
"Things are moving. Discussions are happening," Espinoza tells us.
Wilder and Joshua have been calling each other out publicly for the last year -- with Wilder recently saying he'd even fly to England to fight Joshua on his home turf.