All five players are still young enough to feature for Western Province U21 as they look to make it three consecutive national titles in the SA Rugby U21 Cup, which kicks off with a coastal clash against Hollywoodbets Sharks U21 at City Park on Saturday.
Mars and Smith are currently part of the Junior Springbok squad that is preparing to compete in the Rugby Championship U20, which will take place at the Nelson Mandela Bay Stadium in Gqeberha in the coming weeks.
Outside back Mars, flyhalf Smith, flank Fuller and tighthead prop Porthen have already got a taste of senior rugby, having featured in the Carling Currie Cup last season, with Mars also scoring on his Stormers debut in the Champions Cup clash with Harlequins in London in December.
Director of Rugby John Dobson said that securing the signatures of these five homegrown stars underlines the intent of the contracting model and should give fans every reason to be even more excited about the future.
"We have seen the benefit of securing the cream of our local talent in recent years, with the likes of Damian Willemse, Salmaan Moerat and Sacha Feinberg-Mngomezulu all coming through the ranks here before going on to represent the Springboks," he said.
"These five players represent the next generation to take our team forward and thrill DHL Stormers fans, along with the likes of Paul de Villiers, Gino Cupido and Imad Khan who have all committed their futures as well," he said.
Dobson added that with the SA Rugby U21 Cup kicking off this week, there will be more talent coming through the conveyor belt.
"We have one of the best schools system in the world and although it is not always possible to keep every good player from the region, we are focused on strategically bolstering our senior squad with young talent in the positions we require it.
"We have seen incredible success from the Western Province U21 side over the last two years and hope to see more of the same this year, with those players graduating through the system to make themselves household names for the Stormers."
The Stormers have further bolstered their squad ahead of the 2025/26 season with the big-name signing of Ruan Ackermann as the flanker returns to South Africa after his eight-year stint with English Premiership side Gloucester.
Western Province have signalled their intent to make a serious push in the 2025 Currie Cup, securing the services of three high-calibre Blitzboks to inject pace, skill, and intensity into their campaign.
The talented duo of Ben-Jason Dixon and Wandisile Simelane have signed contract extensions with the Stormers.
Springbok coach Rassie Erasmus added Stormers No. 8 Evan Roos to his squad for the matches against the Barbarians and Castle Lager Incoming Series, increasing the size of his group to 55 players.
