A visibly uncomfortable Moses attempted to battle through the remaining minutes of the first half and the first couple of minutes after half-time before pulling the pin and leaving the field to be replaced by North Queensland's Tom Dearden.
An MRI scan taken in Sydney on Saturday diagnosed Moses with a high-grade muscle tear in the lower leg, for which the typical recovery time can be anywhere between three and six months.
A recovery timeline has not yet been set for Moses, and it will not yet be clear whether the injury will impact his NRL pre-season preparation.
It is nonetheless a big blow to the Aussies' World Cup campaign, which began with a very hard-fought 24-22 win over New Zealand in Sydney on Thursday night.
Dearden is expected to assume Moses' place in the starting XIII, with Canberra Raiders rising star Ethan Strange called up to the 23-man squad as an injury replacement.
"Mitch made a wonderful contribution to our World Cup preparations during the camp in Sydney and very bravely tried to play through the injury until he eventually had to come from the field on Thursday night," head coach Kevin Walters said.
“He is naturally disappointed at the outcome today and the fact that he tried to stay out there when he was clearly injured shows just what it means to him to represent his country and play in the Kangaroos jersey.
"We wish Mitch all the best with his recovery.”