Megastar Amitabh Bachchan rates Hollywood actor Robert Downey Jr. as one the best in the industry, but feels "Chaplin" star has not got his due.

"This afternoon as we run through the list of films that appear on the TV screen, we suddenly stop at 'Chaplin' the film directed by Richard Attenborough, with that master with the camera Sven Nykvist and a host of some of the most brilliant actors from the world of cinema, " Amitabh posted on his blog.

"And playing the lead role, that actor who many rate as the best, well I certainly do, Robert Downey Jr. What a performer and what an actor! An actor I feel that has never been given his due. One that perhaps strayed a little due to his drug abuse, but one that has come out of that successfully and still continues to surprise us in film after film, " he added.

Downey Jr, 46, made his screen debut in 1970 at the age of five by appearing in his father's film "Pound" and since then he has featured in string of films like "Iron Man", "Charlie Bartlett" and "Sherlock Holmes" amongst others.

But there was a dip in his career between 1996 and 2001 as he was frequently arrested on drug-related charges and went through several drug treatment programs.