Born in Aberystwith, Jones is a former Llandovery college player who represented Llanelli in the Premiership before making his Scarlets debut, where he has made 28 appearances so far, including seven from the bench in Heineken Cup matches.
The 20-year-old tight-head or loose-head replaces Ospreys prop Adam Jones who has been released after results of medical screening on a calf problem this morning led coaches to decide they would not wish to risk him against the Wallabies.
"Rhodri is an impressive youngster who can play on both sides of the scrum and is definitely one for the future in terms of our long term planning towards the 2015 Rugby World Cup," said Wales assistant coach (forwards) Robin McBryde, who had direct involvement with Jones during his time on the Scarlets coaching staff last season.
"He is developing well and is a physical specimen who has all the attributes and the values that you need to succeed at this level.
"I have spoken to Matthew (Rees) this week about Rhodri as an international prospect, as well as the other staff at the Scarlets, and they rate him highly.
"Rhodri is one of those players who is very easy to coach, he will benefit hugely from his time with us and not let anyone down if called upon."
Rhodri Jones (LLANELLI SCARLETS - Uncapped)
DoB: 19.1.91. 6'3" / 1.91m. 18st 12lbs / 120kgs