AC Milan's Kaka appears set to step-in for injured Ronaldinho as World champions Brazil face Peru away in a 2006 World Cup qualifier on Sunday.

Kaka began Thursday afternoon's practice match in the first team against the reserves -- which under coach Carlos Alberto Parreira has become a reliable indicator of the likely line-up for the game itself.

"It will be the game of my life," Kaka told reporters.

"If I really do play, it will be my first start for Brazil. I will never forget it.

"I played in the friendly against Jamaica [in October] but this is official, it's different. I'm treating this game as a final."

Ronaldinho also missed Brazil's opening match against Colombia through suspension in September and was replaced on that occasion by Alex, who plays for Brazilian championship leaders Cruzeiro.

But Kaka came on as a second-half substitute and scored the winner in a 2-1 victory with his first touch of the ball.

First choice goalkeeper Dida -- Kaka's team mate at AC Milan -- missed the training for the second day running with back pains but team doctor Jose Luis Runco said he would be fit for the match in Lima.

Brazil will also be without injured Real Madrid left-back Roberto Carlos, who Parreira admitted would be badly missed.

"He's enjoying the best form of his career, he's mature, he's got quality, technique, tactical positioning and intelligence," Parreira said.

"He knows the position better than anyone.

Junior, who plays for Parma in Italy's Serie A, is the automatic replacement.

"Obviously, it's difficult to substitute such a good player but I think Junior will do the job," Parreira told reporters.

Brazil have a maximum six points from two games in the marathon competition, which finishes in October 2005.

Peru have three points.