The Jillaroos have kicked off their Rugby League World Cup campaign with a 40-0 win over a brave Samoa side on Friday night in Sydney.

The hosts entered the contest as unbackable favourites, much like for the tournament itself, but didn’t have it all their way in a tight first period.

But the floodgates opened after Jamie Chapman went over in the corner in the 10th minute.

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Julia Robinson, Shaylee Bent and Keeley Nizza scored in a nine-minute purple patch before Olivia Kernick emphasised the Jillaroos’ clinical dominance for a 28-0 half-time lead.

Keilee Joseph scored the only try of the second half against Samoa, who defended their hearts out and repeatedly stopped the Aussies.

But the Jillaroos didn’t help their cause with some sloppy errors appearing in their game.

Laikha Clarke was millimetres away from a breakthrough try for Samoa on the back of an Australia error and tackle after an impressive effort.

The prop bobbled a pass seven metres out but caught it and immediately turned to crash through multiple defenders, only to knock on as she dived for the line.

Samoa kept knocking on the door in the final minutes and withstood more from the Jillaroos, continuing to shut out Dally M medallist Tamika Upton.

“We have talked about it again and again tonight but I have to say just one more time the defence of this Samoa team has been inspirational,” Emma Verran said on Channel 7.

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“You can see they’re out on their feet out there but they are not giving up. They’re representing their country and culture with such pride.”

Andrew Voss said: “I reckon we just all get up and clap for a minute to say how good they’ve been.”

Moments later Samoa’s 18-year-old star Freedom Crichton Ropati shot out of the line and hammered Tiana Penitani Gray.

But the pressure finally counted for the Jillaroos as Upton ran at Samoa and sent Jess Sergis through for a stress-relieving try.

“We have to call what we see — there’s a lot of work to do for the defending champions,” Voss said.

“This second half has been nowhere near their best but the scoreline is convincing, quite obviously.”

Verran assessed: “(Samoa) were such a brick wall, just causing the Jillaroos to stumble their way through at times.”

Jillaroos captain Isabelle Kelly conceded she was caught off guard by Samoa’s toughness.

“That was really tough, I just want to congratulate Samoa. I think they’ve gone away and worked really hard,” the skipper told Channel 7.

“The physicality of it was probably what stood out to me. But we can be a lot better and I think it’s good as a building block for us.”

Kernick agreed Samoa had stepped it up since their last meeting.

“They stayed in it for the whole 70 minutes, that’s where they’ve improved,” she said.

“They’ve got big hitters all over the park. Their physicality is unmatched, I think they’re one of the toughest teams here at the moment — second to Kiwis, I reckon.”

Samoa copped a blow in the dying minutes when centre Sarina Masaga went down on her own, sparking fears of an Achilles injury.

The Jillaroos will face England in Perth next Saturday while Samoa will stay in Sydney to battle Wales.