The Brazil playmaker and 2007 World Player of the Year looked fit and hungry, linked well with Mesut Ozil and Cristiano Ronaldo and managed one effort on goal that flew well wide.
The 28-year-old former AC Milan player had not featured for his club since May and after representing Brazil at the World Cup had surgery on his knee at the start of August.
"I am very happy to finally be back and return to the pitch with my team-mates," he said in an interview with Spanish TV.
"I went through some very difficult moments during this period but at last I think it's over. I didn't know when I would return, if I would return, and I am very happy. I felt really good."
Asked if he was disappointed not to have hit the target with his one chance, he said the victory for the team was important.
He dedicated his return to his family: "Above all to my wife as she knows what I went through."
Kaka should give Real an extra edge in attack and his return is good news for coach Jose Mourinho given the doubts over the fitness of Gonzalo Higuain and the poor form of his strike partner Karim Benzema.
"Obviously he's not yet at peak fitness but it's fantastic news for Real Madrid and I think also for the Spanish league and the world of football," said Mourinho.
"He is a super player and he hasn't been able to show that yet in Spain.
"He played 15 minutes today and he'll be able to play 15 against Levante (in the King's Cup) on Thursday and little by little he'll recover."
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