Davies replaces broken nose victim Tom Shanklin at centre for only his fourth cap in the Test clash with the Pumas in Cardiff.
Davies carries the tag of the 'new Scott Gibbs' after former Scarlets assistant Paul Moriarty, who played alongside Gibbs at Swansea, once said: "Jonathan is probably the closest thing we have had to a Scott Gibbs type of 12 in Welsh rugby for a long time. He has absolute power with the skill to go with it."
The Test rookie has also faced the comparison with namesake and dual-code star Jonathan Davies.
But the young gun believes he can step up and make his own mark in the Wales jersey.
"Scott Gibbs was a great player in his time so to be compared with him is flattering and a privilege," said the 21-year-old Davies.
"I know we've been compared as having similar attributes but I'm not concentrating on being the next Scott Gibbs.
"I've had the name tag of Jonathan Davies as well since I was young. I suppose I had to play rugby - I had no option!
"My parents said they didn't name me after a rugby player but it's been picked up.
"But I've got to look to create my own legacy, play my own game and fulfill my own potential and not be in someone's shadow."
Davies only made his international debut for the Three Feathers on the North America tour last summer but caught the eye with an impressive performance as a replacement in the nervy win over Samoa last Friday to cement his place.
"When Tom got injured, Jon came on and acquitted himself pretty well," said Wales coach Warren Gatland.
"When you bring in a guy, you have to make sure he feels comfortable. Jon is a young kid but there is no pressure on him.
"I want him to go out there, enjoy himself and run hard. He's big, physical and quick and has scored a lot of tries for the Scarlets.
"We've not given him too much instruction as inside centre is his natural position."
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