Sergio Aguero has acknowledged that his international teammate Lionel Messi is irreplaceable but is confident his side can overcome the talisman's absence.

Messi suffered a knee injury for Barcelona last month and is due to miss nine weeks of action, but Aguero is still confident that Argentina can get their World Cup qualifying campaign off to a positive start without him.

"Obviously it is different without him but we can still make a good start," Aguero, fresh off a five-goal haul for City, told La Nacion.

"Messi is Messi, he is irreplaceable. But there is a great team here which can make his absence felt less sharply.

"Now the key is winning, picking up three points. We are playing at home, it is a long time since Argentina has seen us and we have to play well from the start to gain confidence."

Argentina open their Russia 2018 qualifying campaign against Ecuador in Buenos Aires on Thursday before taking on northern neighbours Paraguay in Asuncion on Tuesday.