Possibles captain Matthew Rees has urged his squad to thrive on Friday night's opportunity and put their hand firmly up for international selection.
Rees will lead the Possibles side at the Liberty Stadium in the Wales Senior Trial and his side will be ready to battle against the Probables in front of a packed stadium.
"It's going to be a big physical match but we are all looking forward to it," said Rees who has 58 Wales caps to his name.
"It's a great chance for the boys on the fringe to have a taste of the international environment and everyone will be trying to put their hand up in front of the coaches.
"It's everyone's opportunity to perform on the night.
"The Possibles team are going out there looking to show their worth and trying to make a statement and the Probables want to go out and put in a good performance ahead of that first test.
"The most important thing on Friday is the performance, but I think when you perform well and everyone does things to the best of their ability you would hope the result will come.
"The biggest thing is performing on the day and when you look at the two squads it's going to be a very interesting game.
After a tough personal year, Rees has returned to the game in remarkable form and he can't wait for his opportunity.
"Going back six or seven months I probably wasn't even thinking about playing rugby again, just to get back playing within this season was a massive achievement for myself," he added.
"If I can get on that plane at the end of it all then it's a bonus, it's something I've been aspiring to.
"I've worked hard over the last few months to get my fitness levels back up to international standards.
"But who knows, it's all on this trial and hopefully I'll do enough to get my place."
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When the Wales squad were asked to nominate individuals who played a big part in their early playing days, Wales and Dragons full back and wing Hallam Amos thought of his former Monmouth School rugby coach John Bevan.
Sam Cross and Luke Treharne have been named as co-captains of the Wales Sevens side as head coach Gareth Williams names his 12-man squad to play in the first leg of the HSBC World Series in Dubai next weekend.
Bedwas head coach Steve Law and players Nicky Griffiths and Alun Rees extol the virtues of the close knit club as they prepare to host third place RGC 1404 - who are one place head of them on the Principality Premiership points table - on Saturday.
Many of the Wales squad have said Diolch (thank you) to someone who played an important part in their early playing days by nominating them to be invited to the Wales v South Africa match. One person, Gowerton Comprehensive geography teacher Mr Dean Mason was nominated by two of his former pupils, Dan Biggar and Sam Davies.
The second WRU disability rugby pilot has been delivered, this time in Caerphilly schools, culminating in a festival at the Caerphilly Centre of Sporting Excellence, Ystrad Mynach tomorrow. Plans are in place to set up a Disability Rugby Club in Newbridge to provide long-term playing opportunities.
WRU TV: Hear from inside the Wales camp as Neil Jenkins discusses this weekend's clash with South Africa and how the squad are looking to put in a strong performance to round of the 2016 Under Armour Series