Fetu Samoa, featuring eight debutants, returned to the Women's Rugby League World Cup for the first time since 2008, but lost its opener to Australia 40-0.
Coach Frank Puletua said, "The scoreline didn't reflect the effort as a team."
Australia, pursuing a fourth consecutive title, led 28-0 at halftime after overcoming an untidy opening 10 minutes.
Jaime Chapman scored first in the 11th minute, and Julia Robinson added her 23rd Jillaroos try in 14 appearances seven minutes later.
Shaylee Bent, Keeley Nizza and Olivia Kernick also crossed before the break; Kernick set up Keilee Joseph early in the second half.
Test debutant Jocelyn Kelleher was player of the match, making two try assists and scoring 12 points; Tamika Upton also assisted twice.
"(Jocelyn's) kicking game was amazing, she took her opportunities and we couldn't have asked for more on debut for the Jillaroos in a World Cup," coach Jess Skinner said.
Samoa's defence improved after halftime and created chances, but Laikha Clarke was ruled to have dropped the ball over the line.
A suspected knee injury to Samoa centre Sarina Masaga late in the match added to concerns.
Jessica Sergis scored in the final two minutes, extending Australia's unbeaten run to almost three years.