Argentina team is full of great talents that can make big difference in their team.
Argentina has very important players injured, not only Messi, they also have Lautaro Martinez who is injured
https://buenosairesherald.com/sports/football/argentina/lautaro-martinez-to-miss-argentina-double-header-with-injuryThis means that Argentina's attack will be weak against Brazil. Argentina's great luck is that Brazil is not a strong team at the moment. It is an unstable team that can win or draw. Since Argentina is well positioned in the table, a loss or draw will not harm Argentina. But I don't see Argentina's game against Brazil as being a very incredible game. Both teams have not played well in my opinion.
Argentina has players the can replace Lautaro Martinez if he's injured. Julian Alvarez can replace him perfectly. Argentina and Brazil are well equipped with players to make sure that they can move the team forward if few players are injured. Even if this match isn't going to affect Argentina if they lose or draw, but for that fact it is Brazil they are going to give their best to make sure they don't lose to
Brazil. Remember the last time they met their was really big tension between the two team. Brazil are not doing bad on their own, their players are also in good form. Raphinha, Rodrygo, Vinicius and others are in hot form currently.