After announcing in late October a provisional 30-man squad for the tournament, Ramalho will reveal on Monday the final list, which will be comprised of 23 players.
The knee injury to midfielder Adriano, which will force him to miss the next five months of action, is a recent worry for Ramalho, but the 55-year-old coach noted he is not mulling over the midfielder's replacement.
"If you look at it carefully, there are no doubts," he is quoted by Lancenet as saying. The list was already done, but Adriano got injured and a spot opened up.
"But there is not much research to do. The criteria is that I will choose what is best for the team."
However, Ramalho admitted that Adriano's loss will force him to change his system for the tournament in Japan.
"He is the only one who is good at marking," he explained. "Against someone like [Lionel] Messi, the best player in the world, it will be hard, because Adriano is the only player who has that characteristic.
"The others are different, they are more creative and get more involved in the game. It changes our playing style a bit, we lose a bit when it comes to marking, but we gain a bit in attack."
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