Just seven months after fearing his career was over before it began, Smith has vowed to repay the Brumbies for putting faith in him to make amends for an off-field indiscretion.

Smith faces the biggest test of his brief career, picked in the Brumbies' starting front row for the clash against the Stormers at Canberra Stadium on Saturday night.

If all goes well, the 24-year-old can cement his place in the prop rotation with Wallabies front-rower Scott Sio nursing an ankle injury for the next six weeks.

It caps a remarkable turnaround for South African-born Smith, who was preparing to have his contract torn up in August last year following a bar-room fight in O'Connor.

Making it even more special is that Smith, who made his Super Rugby debut two weeks ago, gets to do with twin brother Ruan and will be lining up against players he grew up with in Cape Town, as well as fellow Paarl Gimnasium graduates, Springboks Jean de Villiers and Schalk Burger.

"At the start of the year I thought I was one of the last-choice props because I was the new guy, I was just hopeful of getting one or two games for the season," Smith said.

"But the opportunity has come and it's surprising. I played all my junior footy in Cape Town. I basically know all of the guys I'm playing against.

"I couldn't ask for a better team to get my first run-on cap against. We always wanted to play for the Stormers, right from when we were small oaks - it was every kid's dream."

Jean-Pierre and Ruan grew up in the Stormers' system and played in the Vodacom Cup with Western Province in 2010 before moving to Brisbane.

The brothers played alongside Stormers props Steven Kitshoff and Frans Malherbe, winger Kobus van Wyk, No.9 Nic Groom and back-up halfback Louis Schreuder.

Stormers skipper de Villiers and 2004 world player of the year Burger went to the same school as the Smith twins.

"There are four old boys from Paarl in this game ... Jean and Schalk were obviously older and we were in primary school but they set an example. It was an inspiration," Jean-Pierre said.

Smith's promotion will be a serious test for the Brumbies' depth as they aim for their fourth consecutive Super Rugby win.

The Brumbies are missing eight players - David Pocock (knee), Tevita Kuridrani (family funeral), Henry Speight (jaw), Fotu Auelua (knee), Christian Lealiifano (ankle), Scott Sio (ankle), Leon Power (knee) and Clyde Rathbone (hamstring).

It means four of the five Brumbies extended squad - Smith, Stephan van der Walt, Lachlan McCaffrey and Michael Dowsett - get their opportunity to shine.

"Ideally you want to use everyone in your squad in a season ... the beauty of this challenge is that you can use everyone," said Brumbies captain Ben Mowen.

"Everyone is getting a go. JP has proven himself ... it's a good reward for him.

"The Stormers will be desperate, their season is on the line. We felt we put a marker down [beating the Waratahs] last week in what we expect, so we have to bring that again."

Jean-Pierre only started his deal this season, but a fight in August last year almost cost him his Super Rugby chance.

Since then Jean-Pierre and Ruan have been trying to earn respect at Brumbies headquarters, helping teach children at Ainslie Primary School every Wednesday and serving their club-imposed punishment.

They were two of only a handful of players to complete every pre-season training session.

Brumbies director of rugby Laurie Fisher backed Smith to shine in the front row alongside Wallabies Stephen Moore and Ben Alexander.

"I like the way [Smith] scrummages, particularly against South African teams and we think his style will suit what is coming at us," Fisher said.