Brazilian Kaka inspired AC Milan to a 4-2 thrashing of Boca Juniors in the Club World Cup final today.

Kaka capped a virtuoso performance by scoring his side's third goal and setting up two for Filippo Inzaghi as the Italians became the first European side to win the revamped tournament.

"This was the one trophy I hadn't won," Kaka told reporters. "It's magical to finally get my hands on it. I can't describe how happy I am. I've won everything now - it's amazing."

A slide-rule pass from the Ballon d'Or winner gave Inzaghi the simple task of firing Milan into the lead in the 21st minute.

Boca equalised moments later through striker Rodrigo Palacio's header but defender Alessandro Nesta volleyed Milan back into the lead five minutes into the second half.

Kaka got on the scoresheet in the 61st minute, beating goalkeeper Mauricio Caranta after a dazzling solo run before squaring the ball to Inzaghi who slid home Milan's fourth.

"I'm not surprised we scored four goals," shrugged Milan captain Paolo Maldini, who will retire at the end of the season after more than 23 years' service for the club.

"We have Kaka. He is always there for the team in games at the important moments. He's the best player in the world."

Milan finished a pulsating final in front of a crowd of 68,000 in Yokohama with 10 men after Georgian defender Kakha Kaladze was sent off in the 77th minute.