Manchester United goalkeeper Sam Johnstone says he and his U21 teammates know they can't rest on their laurels.

Johnstone admits coach Warren Joyce drums into his players to always be switched on.

He told MUTV: "People are watching you now and not remembering you for last season.

"Warren always says before we go out for a game that there could be someone watching in the stands and it's the first time they've seen you and don't know if you're good. So you have to perform and show them.

"I think it's very important to kick on and not just relax because we've won something."