An all-British clash between Brook and Amir Khan remains a strong possibility, but Hearn believes that the Sheffield fighter is in contention for a Las Vegas showdown with the sport's pound-for-pound king.
Hearn told BBC Radio Sheffield: "I think you have to say that Kell is now in the running to face Floyd Mayweather.
"Everyone in the division wants to fight Floyd, but if you hold a world title, then you are more likely to face him than if you don't.
"He's an obvious opponent and Mayweather is a target for 2015."
Brook is expected to make the first defence of his title in December.