As the Red Devils prepare for the visit of West Ham United tomorrow night, Rooney is well aware that England teammate Carroll, on loan with the Hammers from Liverpool, can create plenty of havoc in his side's final third.
"Andy Carroll is a handful," said Rooney.
"I am sure if you ask any defender, they find it difficult to play against someone like that who is good in the air and on the floor.
"He is physical and makes it hard for opponent.
"That type of player doesn't always get all the goals but they can cause trouble up front and create problems.
"I am sure that is what Sam Allardyce wants him to do."