However, Prior believes that the opening batsman's ability means that he is the right man to lead the Test side.
"I don't know the records he is about to break, but there are going to be a few of them," Prior told reporters.
"Playing his 100th Test, he's only just turned 20 or something! He will be probably the greatest England cricketer.
"In my mind, there is no doubt about that - and from a leader point of view, there is no other man I'd want taking us on to the field."
England meet Australia in the third Test at Perth on Friday at 2.30am (UK time).