The 27-year-old, who is a lance corporal in the Royal Scots Dragoon Guards, will earn his first England cap against the world champions at Twickenham.
And Red Rose head coach Lancaster, whose side lost 3-0 during their tour of New Zealand in the summer, has full faith in the Fiji-born back.
“I spoke to the coaching team, this time last year actually, and they said have a look at this guy, and we obviously picked him in the Saxons in January, he played in the Barbarians game in May, so he’s been on our radar for a while,” Lancaster said.
“Obviously he’s had a fantastic pre-season now and he’s hit the season running. There’s a lot of stats that say he’s topping every category.
“He’s 27 years old. We’ve got some guys in the team who are 20 years old, and I think that experience that he’s had, both inside and outside of rugby, means he’s pretty calm.
“He’s diligent, he’s done his preparation, he’s done the detail, he understands his role and responsibility, he’s been excellent.”
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