Deco, Pedro Pauleta, Costinha, Cristiano Ronaldo and Nuno Valente are already on yellow cards and could miss Portugal’s second round clash if they are booked.

"We are going to make five substitutions, as is normal when players have yellow cards. The five won't play, even if Mexico are winning 30-0," Scolari was quoted as saying by Sky Sports on Tuesday.

Portugal have secured their place in the World Cup’s last 16 as they top Group D with six points, two ahead of second-placed Mexico. Angola lie third on one point and Iran have been eliminated as they are in the bottom with no points.

Scolari, who guided Brazil to the 2002 World Cup triumph, said he is confident the substitutes would fill the void left by the five key players.

"I have no concerns about the substitutes, because some of these players were chosen in the first game. I have absolute confidence in all 23 players,” he said.

Portugal will face either Argentina or Holland in the second round and the Brazilian coach insisted he currently cares only for the Mexico clash.

"All I ask from the players is that they give their best on the pitch (against Mexico). That way I can think about who will play in the next round,” he said.