The Netherlands international has scored 19 Premier League goals this season to help fire the Red Devils 15 points clear of second-placed Manchester City.
But Robson, who won two Premier League titles with United, lavished praise on midfielder Carrick for the England international’s quietly influential displays.
And the former England skipper also reckons Rafael has been one of the club’s standout players in a coming-of-age season for the right-back.
“In my mind, there are three players right up there in the reckoning,” he told United Review.
“Obviously, the way Robin van Persie has come into the club from Arsenal and the way he has played makes him a strong candidate, but I believe Michael Carrick and Rafael are both running him very close.
“Michael has had a great season and it speaks volumes that Sir Alex has played him in more or less all our games. He is a very intelligent footballer and has done excellently all season. Rafael has really progressed and has had a great campaign as well, so it’s a close call between those three, for me.”
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