World Cup 2010 - Brazil thrash Tanzania
Midfielder Ramires added the other two goals, his first for Brazil.
Kaka, who suffered niggling injuries in a frustrating first season at Real Madrid, netted his first international goal in nearly a year.
He played the full 90 minutes and produced several characteristic bursts from midfield in an encouraging performance.
Tanzania's goal deprived Brazil of a sixth successive clean sheet. The last team to score against the five-times world champions was Bolivia in October.
"I feel good but I still need to let myself go a little," Kaka told Brazilian television.
The visitors were without Julio Cesar in their starting line-up for the first time in two years.
The Inter Milan goalkeeper was left out as a precaution after hurting his back in a 3-0 win over Zimbabwe.
Brazil went ahead after 10 minutes when Kaka set up Robinho to score with an angled shot.
The hosts created a couple of chances but Brazil rode the storm and made it 2-0 when Robinho tapped in from close range after a cross from Michel Bastos went across the face of the goal.
Kaka added the fourth, scoring with his chest from Maicon's cross in the 76th minute, before Tanzania notched a consolation effort 10 minutes later as Jabir Aziz headed in from close range.
Ramires made it 5-1 by nodding in a Daniel Alves cross in injury time.