Brazil were furious with a challenge on Neymar than threatens to rule the striker out of their quarter-final meeting with Colombia.
The hosts' talisman was clattered by Charles Aranguiz just four minutes into Brazil's eventual win over Chile at the Mineirao Stadium in Belo Horizonte.
"I don't understand how you can do that and not be booked," Brazil coach Luiz Felipe Scolari said after the match.
Neymar was able to continue despite the knock to his thigh and was fit enough to take and score Brazil's final penalty in the shoot-out.
However there remain concerns over the Barcelona player's fitness ahead of Friday's quarter-final.
"We need to evaluate it but we should have three, four or five days to try and make sure he can play the next game," said Scolari.
Neymar said after the match: "We really suffered. It was pure emotion. My tears after the game were of happiness.
"We know that it was not one of our best matches but the desire to win, and get through to the next round, was huge. It was the most I have ever suffered in football.
"Today I had everything. I took a knock, I had cramp. Now all I want to do is rest."
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