Real Madrid star Kaka will be sidelined for at least a month due to the groin injury that he picked up against Barcelona.

It was originally thought the injury was less serious than what it is, and now will have to miss a series of matches, including the trip to Valencia this weekend reported AS.

This means Madrid will be without both their signature signings with Cristiano Ronaldo suspended after last weekend's antics.

It is believed that Kaka will not be rushed as they are keen on allow him to recuperate fully.

A source told AS that, "Kaka is an important player for this project and we are not going to risk a couple of games. If he rests and heals well, then he will be back in the new year."