Rooney has been in stellar touch for the Barclays Premier League champions this season netting 32 goals, and at times single-handedly keeping United's season alive.
'The most important player is Wayne Rooney,' the England manager said. 'He scores lots of goals; he finishes everything.
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'Players need time. Rooney started at Everton at 16 and he has matured. Right now, his form is incredible and I hope he can maintain that level until South Africa.
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'There are three players who are on a different level at the moment. One is [Lionel] Messi, one is Cristiano Ronaldo and one is Rooney. They are a step above everyone else in the world.'
Rooney's team-mate Michael Carrick also hopes Wayne Rooney can maintain the recent form he has shown for United.
As a team-mate for club and country, Carrick is ideally placed to judge how important Rooney is to the England side. And he insists the former Everton striker is the man most likely to fire the national team to glory.
'He's obviously the main man for United and England when he's playing like that,' Carrick said. 'He can lead teams and help them be successful and hopefully he's going to have a big few months.
'It will give the lads a big boost because he's just got that presence, and great players have that. He's got that all-round presence that people respond to.'
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