Ancelotti yesterday said he would rather have the United striker in his team than Messi.
Ancelotti also believes United can cause an upset and beat Barcelona in the Champions League final.
"Everyone goes for Messi but I would take Rooney. Messi is out of this world and maybe he is reaching the level of Maradona. Rooney, however, is closer to the reality of football. He puts his talent out to the rest of the team and this explains the difference between players and outstanding players."
But Ancelotti claimed he would not man-mark the United star, saying: "It means changing our philosophy too much.
"We want to play our football, not just control their skills and ability. Rooney is the key player for United, and the last time against us Ryan Giggs was the best player. He passed three balls and they scored three goals."