Wales will hold the first trial match in 14 years with a Probables v Possibles clash at the Liberty Stadium on Friday May 30.
The Wales Senior Trial will see the two squads go head-to-head in an old-school trial in Swansea with the chance to impress the national squad management and book their place on this summer's tour to South Africa.
Wales assistant coaches Rob Howley and Robin McBryde, who both played in the last Wales trial in 2000 at St Helens, will lead the coaching teams for the Probables and Possibles respectively and will announce their squads on Tuesday.
The two squads will prepare for the clash separately with Howley's coaching team including Shaun Edwards and Scarlets forwards coach Danny Wilson. Neil Jenkins and Cardiff Blues' Dale MacIntosh will join McBryde in preparing the possibles side.
The players won't have long to find out whether they have made the touring party to South Africa with Warren Gatland set to reveal his squad in the post-match press conference.
For those who make the 31-man squad it will be ideal preparation ahead of the two-Tests against the former World Champions according to Gatland.
"It's great that we are able to resurrect the famous Wales trial," said Gatland.
"It's a good opportunity for the players but its also important for us in our short term as well as long term preparation.
"The trial will enable us to work with the extended squad and see those players in our environment as preparations ramp up for next year's World Cup.
"It's a chance for players to experience the set-up and round off a week's training with us in a meaningful match and hopefully put their hand up for this summer's tour.
"We will be announcing the squad to travel to South Africa after the game so it's a great opportunity for players to book their seat on the plane.
"The tour itself is going to be extremely tough and the game will be important in ensuring we don't head into it cold.
"The majority of the squad would not have played for four or five weeks and we need to hit the ground running.
"The Springboks are immersed in Super Rugby right up to the tour and then have a game against a World XV the week before the first test so they certainly won't be under-cooked."
Any profit from the game, together with a modest donation, will be provided to the Welsh Rugby Charitable Trust.