Cristiano Ronaldo and co were not at all convincing in the group stage and scraped into the knockout rounds with a 1-1 draw against Iran.
They had previously edged out Morocco 1-0 after opening their campaign with a thrilling 3-3 draw against local rivals Spain.
But the Portuguese proved at Euro 2016 they can get the results to win a tournament without blowing the opposition away, and they will be optimistic of edging out their South American opponents.
The squad is fully fit and nobody is suspended, but boss Fernando Santos has some big decisions to make.
One is whether to start Andre Silva or Goncalo Guedes up front alongside Ronaldo?
The other is how does the midfield look – with William Carvalho the only nailed on starter.
Bernardo Silva, Joao Moutinho, Ricardo Quaresma, Joao Mario and Adrien Silva are the main contenders to join the defensive midfielder.