Didi Hamann admits keeping Manchester United ace Cristiano Ronaldo quiet is key to any potential success for Manchester City in today's derby.

"We will have to make sure we are tight and compact and we must help each other," said Hamann, who will need to offer support to City's full-backs today. "Ronaldo has become a joy to watch in the past couple of years. If you can stop him getting the ball he can't do any damage.

"But they have so many players who can make things happen, so you can't put two players on Ronaldo because that will leave another player exposed and he will do the damage."