Messi has scored all five of Argentina's goals in victories over Algeria and Austria, helping his side secure qualification for the knockout stages with a game to spare. With top spot in the group already guaranteed, Scaloni has decided to rest his captain from the starting line-up.
Speaking to Argentine radio journalist Enrique Macaya Marquez, who was covering his 18th World Cup, Scaloni gave a clear answer about Messi's role.
"Leo will start on the bench," Scaloni said.
"I'm answering because you deserve a sincere answer.
"Leo will come in a little bit later."
Although several changes were expected, Scaloni rejected the suggestion that Argentina would field a weakened team.
"Those that are playing tomorrow deserve to play, they are part of the team," he said.
"All the effort we've put in in training is because of them, that's why we're here. They are making every effort when they're not playing."
Scaloni added that he wanted every player to receive opportunities when possible.
"I'd love to give everybody minutes and when I have the chance I do and it's because they deserve it. They are fantastic players too.
"The dream as a coach is to have the team perform the same way, independent of the players who comprise the team."
The Argentina coach insisted his side's mentality would not change despite already securing first place.
"If you are wearing the jersey and playing it doesn't matter if you're playing in a game of significance for the points or not. You're going to do your best to win, nothing changes. We're in the same way as we were on day one."
Argentina were preparing to face a Jordan team already eliminated after losing their opening two matches on their World Cup debut. Scaloni expected Jordan to defend in numbers and said his players were ready to adapt if required.
"Jordan normally play with five defenders and we're open to the possibility that, if we're facing some difficulties, we might have to move slightly differently," he said.
"We might be prepared to do something differently if things are challenging, depending on how our opponent plays."
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