The Real Madrid forward poses an enormous attacking threat and heads into the tournament in superb form, having scored 60 goals in all competitions in the 2011/12 season.

Loew is aware of the former Manchester United man's qualities, but insists he cannot entrust a player with the sole responsibility of tracking his movements.

"If I will have Philipp Lahm marking Ronaldo? I will decide where he will play only when I arrive in Poland," Loew told reporters.

"There is no sense in putting one player on Ronaldo all the time.

"I would need three or four players to stop him. I do not want one-on-one situations against him."

Germany will play against Portugal in their Euro 2012 opener on June 9 before matches with the Netherlands and Denmark.