Kaka says he enjoys the responsibility of being AC Milan's prime player.

As Milan to play their first game in the Club World Championship, Kaka said: "This is a very important trophy for the South Americans, so myself and my teammates will do everything we can to win and write our name in the history of football."

He was in the side that lost to Boca Juniors in 2003, but four years on he has become a key figure in the Rossoneri line-up.

"I like responsibility. I know I am here and what is expected of me, so it is true that things are different for me compared to the last time I played in this tournament," said Kaka, who could face Boca Juniors again in the Final.

"Right now we are focusing only on the semi-final. As for the rest, I don't like the idea of revenge. In 2003 Boca won and that is all there is to it. We have to look forward."