The pair are due to combine in the Manchester City engine room at Eastlands on Sunday as Sven-Goran Eriksson's new-look Blues face the acid test of their surprise Barclays Premier League start against local rivals United.
"Sooner or later you will see Michael Johnson playing for England," said Hamann.
"He has done ever so well this season. He trains well, he listens and he wants to improve all the time.
"He scored a great goal on Wednesday and he has a fantastic career ahead of him."
If Johnson is City's rising star, Richards is an established one.
The youngest defender ever to play for England, Richards is a certainty to figure for his country against Germany on Wednesday, when Hamann will naturally be cheering for the visitors.
Yet the former Liverpool star will also have half an eye on his young team-mate, the kind of physical specimen Hamann has rarely come across in all his years in the game.
"Everyone knows what a prospect Micah is," he said.
"He is the most physical, athletic player I have ever seen - and he is only 19.
"All he can do is improve. I know he played right-back most of last season but his best position is definitely centre-half."