Wales coach Warren Gatland has made four changes to his team for Saturday's Test against Argentina in Cardiff.
Uncapped Cardiff Blues centre Cory Allen, 20, replaces injured Scarlet Jonathan Davies with Dan Biggar in for Rhys Priestland at 10.
Scarlet Rhodri Jones replaces injured tight-head Adam Jones (calf) and Justin Tipuric comes into the back-row with Dan Lydiate (ankle) ruled out.
Loose-head prop Gethin Jenkins will win his 100th Wales cap.
Davies (chest) and Adam Jones are both ruled out of the rest of the autumn series after picking up injuries in the bruising 24-15 defeat by South Africa.
Blind-side Lydiate was also injured against the Springboks, so captain Sam Warburton switches flank, with Tipuric taking over at open-side.
Scarlets props Rhodri Jones and Samson Lee plus Dragons back Hallam Amos and Tom Prydie were called in to train with the squad earlier this week to cover injuries.
Goal-kicking wing or full-back Prydie has returned to his region for further treatment on a hamstring injury, but the other three have been retained in the squad for the remainder of the campaign.
Gatland said the one unenforced change - Biggar for Priestland at fly-half - was planned before the start of the autumn series.
"It was always our intention to give Dan and Rhys one game each at the start of the series and it's Dan's chance this weekend," Gatland said.
However, the selection of Allen at centre and Rhodri Jones at tight-head were not predicted.
Wales went into the autumn series without British and Irish Lion Jamie Roberts (ankle).
Scott Williams took over from Roberts and now Allen will join him in an all-new midfield partnership against the Pumas.
Allen's promotion means Osprey Ashley Beck remains on the bench after he impressed as Davies' replacement against South Africa.
Sevens specialist Allen has played only 10 senior games for the Blues, including the Heineken Cup win over defending champions Toulon.
Allen counts Roberts among the major influences on his career and said he would like to emulate the powerful, off-loading style of dual-code New Zealand star Sonny Bill Williams.
"It's still a bit of a shock I got in the squad and [as for] starting this weekend - I can't wait. [My ambitions at the start of the season] were just to break into the Blues squad," Allen told BBC Wales.
Prop Jones made his international debut against the Barbarians in 2012 and came on as a replacement in the 22-18 win over Japan in June.
"We have made a number of changes due to injury, but it's a great opportunity for players we have been very impressed with," added Gatland.
"For Cory it will be his first taste of international rugby and for Rhodri [Jones] a chance to gain more experience.
"Justin [Tipuric] played very well off the bench last weekend and Dan's injury gives him the chance to start the game."
Gatland also paid tribute to prop Gethin Jenkins.
The British and Irish Lions loose-head, who made his debut against Romania in 2002, joins Gareth Thomas, Stephen Jones and Martyn Williams as players with a century of caps for Wales.
"Saturday will be a huge occasion for Gethin and a fantastic milestone," said the Wales coach.
Team to face Argentina
Wales: Leigh Halfpenny (Blues); George North (Northampton Saints), Cory Allen (Blues), Scott Williams (Scarlets), Liam Williams (Scarlets); Dan Biggar (Ospreys), Mike Phillips (unattached); Gethin Jenkins (Blues), Richard Hibbard (Ospreys), Rhodri Jones (Scarlets), Bradley Davies (Blues), Alun Wyn Jones (Ospreys), Sam Warburton (Blues, capt), Toby Faletau (Dragons), Justin Tipuric (Ospreys).
Replacements: Ken Owens (Scarlets), Paul James (Bath), Samson Lee (Scarlets), Luke Charteris (Perpignan), Ryan Jones (Ospreys), Lloyd Williams (Blues), James Hook (Perpignan), Ashley Beck (Ospreys).