Mason, who has switched codes by swapping Hull KR for French club Toulon, has been named among the replacements for the first leg of the Barbarians' two-game tour.
It will be the first time the 31-year-old former Australia league international has played a union match since leaving school.
Italy star Sergio Parisse leads the side with former England wing Paul Sackey on the bench.
Prop Davit Kubriashvili is the first Georgian to play for the Barbarians while Erik Lund becomes the first Norweigian to pull on the jersey.
Their selection means 31 different nationalities have represented the team.
Team: N Jeanjean (Brive); P Sackey (Toulon), B Baby (Clermont Auvergne), M Bastareaud (Stade Francais), T Visser (Edinburgh); F Michalak (Toulouse), R Pienaar (Ulster); S Perugini (Aironi), L Ghiraldini (Benetton Treviso), D Kubriashvili (Toulon), E Lund (Biarritz), P Tito (Cardiff Blues), J van Niekerk (Toulon), G Smith (Toulon), S Parisse (Stade Francais, capt).
Replacements: S Bruno (Toulon), C Hayman (Toulon), Q G (Aironi), M Williams (Cardiff Blues), S Tillous-Borde (Castres Olympique), W Mason (Toulon), S Rabini (La Rochelle).
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