"When I went to Stevie's wedding, he said how impressed he'd been by David when they met up with the England squad," revealed Warnock to the Lancashire Evening Telegraph.
"He hadn't realised just how good he was until he trained with him for the first time.
"But I said Bents does it every day in training - I didn't think he'd lift his game just because he was with the England squad.
"Every day he's fantastic in training.
"I didn't know much about him but then, when you come and train with him on a day-to-day basis, you realise he's got the ability to go up a notch.
"He enjoys the photo-shoots and things like that but it never side-tracks him from his football; that's his main priority.
"To get back into the England team is his aim and everyone knows he can achieve that. He's a confident boy and if he puts his mind to it he knows what he can achieve."