New Zealand will have to seek permission from Queen's Park Rangers to secure captain Ryan Nelsen's services if the Oly-Whites defeat Brazil. Nelsen is due to leave with QPR for a 10-day training camp in Germany on Saturday.
But, if the Samba Boys are defeated and the All Whites finish above Belarus and Egypt in pool play, they would play a quarter-final game on Sunday.
New Zealand coach Neil Emblen said he would "hope'' QPR boss Mark Hughes would see that Nelsen was getting good quality games at the Olympics.
"The preparation he's getting here is really good for Ryan at this stage of his career''.