Kaka has been a peripheral figure in Madrid for much of the campaign but scored a good goal in Saturday's 2-1 win at Deportivo La Coruna.
The Brazilian has started just four games in La Liga since September but thinks that he can be important for Madrid coach Jose Mourinho in the next few weeks.
He told AS: "I am improving, everything is getting better. The coach needs me now and I have to be at my best for this crucial part of the season.
"In the first half, we were a little anxious and we made too many mistakes. We got better in the second half and in the end, have taken three very important points ahead of a testing week of matches."
Madrid face Barcelona at Camp Nou on Tuesday in the second leg of their Copa del Rey semi-final clash, with the tie finely poised at 1-1.