Messi scored four times as Argentina finished top of Group F, and Sabella believes that the Barcelona forward is as important to the team as Diego Maradona was to the side who recorded victory in the 1986 tournament.
"Messi is playing an amazing World Cup, but that is what everyone expected," the Argentina coach told reporters. "He expected it, so did his colleagues and so did all of Argentina in general.
"We are happy for him and the team. Is he as important to us as Diego Maradona was in 1986?
"Maradona was a very important player at that time and Messi is important as well."
Argentina meet Switzerland in the last 16 on Tuesday.