Germany's players will need steel helmets for protection when Portugal's Cristiano Ronaldo lines up to take free kicks in their Euro 2012 Group B match in Lviv on Saturday, Germany assistant coach Hansi Flick said.
Ronaldo packs a powerful strike from dead-ball situations and the Germans have been told to minimise the risk of commiting fouls outside the box in one-on-one situations.
"At 20, 25 or even 30 metres we need to be clever in the one-on-one situations. Ronaldo has an exceptional free kick quality."
Germany also play Netherlands and Denmark in their group.
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