– that’s the sort of experience you can’t give him on the training ground. You’ve got to go and experience that and he did it."
Johnstone has captained the England Under-19s and also been part of his country's Under-21 squad, illustrating how highly he is regarded at international level.
Tall, athletic and very agile, the son of former Preston keeper Glenn commands his area with authority and is a fine shot stopper. He has also earned something of a reputation for saving penalties after his heroics ensured United won the Barclays Premier Reserve League play-off against Aston Villa in a shoot-out at Old Trafford in 2012 and he also made a crucial spot-kick stop to help the Reds qualify from the first phase of the new Under-21 division last season.