Carr is set to be honoured with a star-studded testimonial next Wednesday.
Carr, 59, said: "I guess Rio nicks it because he had it all, even as a kid.
"He was quick, he could jump, pass and defend.
"He was a superb athlete and had reams of natural talent.
"I want to give him the No 6 shirt next week because he is England captain and that number belonged to another special England skipper still much loved at this club.
"I hope it could be the secret weapon to bring the World Cup back this summer."