he was only going off past instances. remember this-
evans with a high reckless kick on to drogba's chest area. ends up breaking 1 of drogba's ribs.
end result= free kick to utd & a yellow card to drogba! yes, u heard right.
so when nani did it against Madrid, he logically assumed utd would get a free kick & arbeloa would be booked.
Get a life!