Kleyn was born in Johannesburg but joined Munster in 2016 and qualified for Ireland through residency. He played five tests, including two at the 2019 Rugby World Cup in Japan, which were also his last.

His form for Munster this season has caught the eye as he played a key role in beating his former side the Stormers in the final of the United Rugby Championship last month.

World Rugby introduced a rule change in 2021 that allows test-capped players to represent a second national team if they are eligible after a period of three years of inactivity with their original country.

The competition among the locks in the Springbok squad is fierce, with Lood de Jager, Eben Etzebeth, Marvin Orie and RG Snyman named in the training squad, while loose-forwards Pieter-Steph du Toit and Franco Mostert are also accomplished in the second row.

The Bok training camp will be staged in Pretoria from next week, with the team’s Rugby Championship opener against Australia at Loftus Versfeld on July 8.

Defending champions South Africa have been drawn in the same pool as Ireland and Scotland at the Rugby World Cup in France in September and October, with two teams qualifying for the quarter-finals.

Bok training squad:

Props: Thomas du Toit, Steven Kitshoff, Vincent Koch, Frans Malherbe, Ox Nche, Trevor Nyakane

Hookers: Joseph Dweba, Malcolm Marx, Bongi Mbonambi

Locks: Lood de Jager, Eben Etzebeth, Marvin Orie, RG Snyman, Jean Kleyn (subject to World Rugby approval)

Loose Forwards: Pieter-Steph du Toit, Siya Kolisi, Evan Roos, Kwagga Smith, Marco van Staden, Duane Vermeulen, Jasper Wiese

Utility Forwards: Jean-Luc du Preez, Deon Fourie, Franco Mostert

Scrumhalves: Faf de Klerk, Jaden Hendrikse, Herschel Jantjies, Cobus Reinach, Grant Williams

Flyhalves: Manie Libbok, Handre Pollard, Damian Willemse

Centres: Lukhanyo Am, Damian de Allende, Andre Esterhuizen, Jesse Kriel

Outside Backs: Kurt-Lee Arendse, Cheslin Kolbe, Willie le Roux, Makazole Mapimpi, Canan Moodie.