Manchester United great Wayne Rooney has heaped praise on summer signing Lisandro Martinez.

The centre back arrived from Ajax in the recent window and has put a testing start behind him to become one of United's most consistent performers.

Martinez will look to carry his exceptional form at club level over to the international stage when he steps out at his first World Cup for Argentina next week.

Rooney said: "I really like Lisandro Martínez. Watching him for Manchester United recently, he is really composed and aggressive.

"He is perfect for international football and will be a big player for them."