Manchester United want Dean Henderson to sign a new contract before sending him out on loan.
The goalkeeper did not join his United teammates when they left for Australia on Sunday.
ESPN says the Red Devils are pressuring Henderson to commit his future to the new club, with the view of loaning him to Sheffield United.
Henderson, 22, played an integral role in helping the Blades secure promotion to the Premier League.
Blades boss Chris Wilder has spoken publicly of his desire for Henderson to re-join the club.