McClaren believes Rooney can become the best player at the World Cup in South Africa.
“I think Rooney has been the key man for a couple of years with Manchester United, and he is coming to the fore for England,” said McClaren.
“You talk about there being six or seven teams that can win it. There are also six or seven players who are world-class who can win the title of the best player at the World Cup and Rooney is certainly one of them. To lose him would be a big blow. I hope he stays fit.”