With Messi's international future in doubt, his recent absence during the international break brought further questions around his commitment to the South American giants.
However, the number 10 jersey was notably not awarded to any newcomers in the squad, which Scaloni was prompted about.
"There is only one answer for your question: Every player who was in the World Cup kept his number, the ones who came here," he told reporters.
"In this time, the 10 shirt belongs to Messi, and it will stay this way until he decides if he will continue with us or not.
"We aren't closed to that chance so I chose to keep this number for him. In the future we will see, but if you look at the players who played the World Cup you will see they kept their numbers.
"And we wait for the future to see what happens, but so far no one is using the 10 because it is exclusive for him and that is my decision. There is nothing else about this."
Per TNT Sports, via Mundo Deportivo Messi opted to step away from the national team in August.
His plan was to see how the side develops over the rest of the year before making a final decision on his international future.
The 31-year-old once again endured heartbreak with the Albiceleste at the 2018 FIFA World Cup, as Argentina disappointed before being knocked out by eventual champions France in the last 16.
He hasn't tasted success with the team since the 2008 Olympics.