Ulster and Ireland legend Rory Best will bow out of the sport after captaining the Barbarians in their friendly against Fiji on Saturday (kick-off 2:30pm).
The 37-year-old has been named as skipper by head coach Eddie Jones for what should be an intriguing encounter against the mercurial Fijians at Twickenham.
Best will pack down alongside Springboks World Cup winning loosehead Tendai 'Beast' Mtawarira and Argentina's Enrique Pieretto for the clash in London.
There are three of the South African squad that triumphed over England in Tokyo two weeks ago named in the squad, with Mtawarira joined by international team-mates Makazole Mapimpi and Lukhanyo Am in the squad.
It is a South African heavy squad, with seven named beyond the three World Cup winners, including experienced fly-half Morne Steyn among the replacements.
Bruising French centre Mathieu Bastareaud is also included as he prepares to head off to the US to join Major League Rugby side Rugby United New York.
There will be some familiar faces for Ulster fans beyond Best, too, with former Ospreys lock Tyler Ardron packing down alongside ex-Bordeaux man Luke Jones, while No.8 Josh Strauss is formerly of the Glasgow Warriors.
Replacement prop Campese Ma'afu faced Ulster in the Heineken Cup with the Northampton Saints as well.
Barbarians squad to face Fiji
15. David Havili; 14. Dillyn Leyds, 13. Mathieu Bastareaud, 12. Andre Esterhuizen, 11. Makazole Mapimpi; 10. Curwin Bosch, 9. Joe Powell; 1. Tendai Mtawarira, 2. Rory Best (captain), 3. Enrique Pieretto; 4. Luke Jones, 5. Tyler Ardron; 6. Pete Samu, 7. Marco van Staden, 8. Josh Strauss.
Replacements: 16. Andrew Makalio, 17. Campese Ma'afu, 18. Hencus van Wyk, 19. Angus Cottrell, 20. Matt Philip, 21. Jano Vermaak, 22. Lukhanyo Am, 23. Morne Steyn.