Rashford scored 13 times in all competitions for United last term, but struggled for action in his favoured centre-forward position, and was criticised by Red Devils boss Jose Mourinho on a number of occasions.
Crouch has said that the youngster "had a hard season", but the Stoke City forward is looking forward to watching him in action in this summer's competition.
"We can't forget he's only 20. He was playing up front for Manchester United at 18 so what he's achieved so far isn't really normal," Crouch told the Daily Mail.
"Jack Butland always comes back to Stoke after international games raving about the quality of his finishing. He's had a hard season and I just hope his confidence hasn't been dented.
"He is such an exciting player - the type who will get you out of your seat."
Rashford scored from a long-range effort in England's 2-0 win over Costa Rica last time out.