Real Madrid's Kaka (L) celebrates his goal against Athletic Bilbao during their Spanish first division soccer match at the San Mames stadium in Bilbao April 9, 2011. [Photo/Agencies]

MADRID - Real Madrid midfielder Kaka on Monday promised to try and pay back the faith the club has shown in him.

Kaka's two seasons at Madrid have been a major disappointment: since making a move worth almost $100 million from AC Milan, he has suffered a serious of pelvic and knee injuries and has played less that 40 league matches.

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However, his two goals from the penalty spot against Athletic Club Bilbao on Saturday have given him confidence that he has recovered form and fitness at the key moment of the season and Kaka now wants to show that he is worth the money the club paid for him.

"My knee responded well and I am very pleased about that, I was able to play with more freedom and enjoy my football," he commented in sports paper Diario AS.

"Now is an important moment for Real Madrid, we have the final of the Copa del Rey and probably we will play the semi-finals of the Champions League. They will be two months that will determine the result of our season," added Kaka.

"I want to enjoy my football and I feel that I have a debt to Real Madrid, which annoys me a little bit because I have not had the chance to live up to expectations," commented Kaka, who will have the chance to do that when his side entertain FC Barcelona in the Primera Liga next Saturday.

The two clubs will meet four times in a three week period if they both reach the semifinals of the Champions League and although next Saturday's encounter is probably the least important of the four, given that Barcelona have an eight point lead in the BBVA Primera Liga, Kaka insists Madrid can't give up.

"You have to always try and beat Barca, we have to prepare the game looking to win it. We are capable of beating them both in the Santiago Bernabeu and also in the Camp Nou," he said.

Kaka was asked if he was happy at Real Madrid and he insisted that he was.

"I want to stay at Real Madrid, I need to play and I am working to do that and although people say a lot of things, I know what is the truth and it is that I am working to stay at Real Madrid," he concluded.