Asciano Group is bidding with CBH Resources in Western Australia for a contract to transport grain.
The port and rail operator is competing for all three parcels of the A$700m (US$621.39m) contract, which will enable the transportation of A$100m (US$88.77m) of grain a year.
CBH aims to increase the rail freight delivery from 50-70%.
The contracts will be awarded by the end of the year.
QR National subsidiary Australian Railroad Group currently operates the service.