Charlton was asked to name his all-time greatest United XI by the Daily Mail.
"We've had some magnificent centre halves down the years," says Sir Bobby. "But these two form the most formidable pairing of all."
Charlton's greatest United XI:
Schmeichel - Byrne, Vidic, Ferdinand, Dunne - Edwards, Robson, Charlton - Cantona, Law, Best