Rooney said it was easy to turn the tables on van Persie and catch him out.
Asked to name his easiest target in the United squad, Rooney said: "I'd have to say Robin. He's not the brightest!
"As much of a good footballer he is, he's definitely not the brightest off the pitch and it's just easy to get to him.
"There's a few who like to joke around. There's no-one who stays really quiet and out of it."