Robson rates RvP as United's star turn.
He told the Manchester Evening News: "Robin van Persie's had a little bit of a dip in form in that he hasn't scored as many goals but what people have got to remember is that it was a fantastic run he was on.
"To try and replicate that for the whole season is very difficult - especially when you're a striker. You nearly always get a little bit of a patch where you go six or seven weeks without scoring a goal. You'll hit a ball and it's going in the corner and the keeper makes a great save or it hits a post.
"Hopefully his goals for Holland and the one at Sunderland is him back on track."