MANCHESTER, March 23 (Xinhua) -- Lionel Messi said on Friday that he is "optimistic" about being fit for Argentina's international friendly against Spain in Madrid next week.

The Barcelona forward missed his team's 2-0 victory over Italy at Manchester City's Etihad Stadium on Friday because of a hamstring strain.

"I have been having trouble with the hamstring for some time now, so we decided to rest to prepare for what is coming. I'm optimistic about playing against Spain on Tuesday," Messi told Argentine television channel TyC Sports.

Meanwhile, the Argentine Football Association (AFA) said that striker Sergio Aguero has been cut from the Albiceleste squad after failing to recover from a knee problem.

Aguero sustained the injury while training with his club Manchester City on March 11 and has not played since.

"Sergio Aguero has been released from the squad to continue his recuperation," the AFA said in a brief statement.???