The manager admitted he was surprised to learn that Ferdinand was to be included in Roy Hodgson's squad for the forthcoming international matches against San Marino and Montenegro.
"I was as surprised as anyone when I heard that [Rio was being called up]," the boss told reporters on Friday at his pre-match press conference. "I need to speak to our doctor… we prepare Rio in certain ways and he has certain treatments he has to go through.
"The procedures have been the same all season, which has given him fantastic performance levels when he’s playing for us. We have to consider that and Rio is considering that. And we’ll see what the outcome of that is."
The 34-year-old centre-back has been in brilliant form for United this season and Sir Alex is keen to ensure that his fitness is not compromised by over-playing.
"[Rio] has to make sure he’s going to be okay in terms of the number of games he plays," added the boss. "We’ve been doing that for two years with him. And it’s worked - the way we’ve detailed his training programmes and given him the treatments he needs for the various complaints he has in terms of his back and groin and things like that. So far it’s worked very well. We have to look at all these things before Rio decides."
International breaks are an occupational hazard for top managers at the best of times, but with the run-in now in full swing Sir Alex is keen to get