The Warriors league team beat Penrith Panthers 42- 20 in Auckland on Sunday to keep alive their hopes of making the final eight in the NRL competition.
But Warriors fullback Wade McKinnon has been put on report for spitting at a linesman after the Panthers scored a controversial try.
The incident happened after McKinnon protested that the final pass by the Panthers had been forward.
Television replays show McKinnon spitting but do not show exactly where the linesman was at the time.
The Warriors scored seven converted tries.
It was the last home game for veteran forward Ruben Wiki.
The Warriors win means they are still in with a chance to make the top eight in the Australasian club competition.
They are now ninth on the table but have a chance to make the top eight if they beat the Parramatta Eels in Sydney next week and one of the teams immediately above them on the table loses.