Influential South Africa duo Faf de Klerk and Pieter-Steph du Toit have been ruled out of Saturday's series decider against the British and Irish Lions due to injury.

Scrum-half De Klerk has a muscle strain and has been replaced by Cobus Reinach, while flanker Du Toit sustained a shoulder problem in last weekend's second Test, which the Springboks won 27-9 to level proceedings.

Franco Mostert will switch to the back row to take the No 7 jersey vacated by Du Toit, with Lood de Jager recalled at lock.

World Cup-winning No 8 Duane Vermeulen does not make the squad after joining the camp following an ankle injury, while prop Ox Nche again misses out due to a neck issue.

Veteran out-half Morne Steyn has been named among the replacements

Morne Steyn, who kicked the series-clinching penalty against the Lions in 2009, could win his first Test cap since 2016 after being named on the bench.

"This group of players are among a handful of players in the history of South African rugby that have an opportunity to clinch a series against the Lions after winning the Rugby World Cup, and every player in this squad understands what a rare honour that is," said Boks head coach Jacques Nienaber.

"I don’t think one needs any more motivation than that to win this weekend. We are preparing for a physical encounter and we know that every small battle will count if we want to win the series.

"This match is as important to us as it is for the Lions, so we know it is going to be tight, and we will have to capitalise on every opportunity we have to score points, and be effective in every area of our game.

"As Springboks, big moments such as these excite us, so we plan to go out there and give everything we have to clinch the series."

The Lions have made six changes with Bundee Aki partnering Ireland team-mate Robbie Henshaw in midfield and Conor Murray dropping to the bench.

South Africa: 15 Willie le Roux, 14 Cheslin Kolbe, 13 Lukhanyo Am, 12 Damian de Allende, 11 Makazole Mapimpi, 10 Handre Pollard, 9 Cobus Reinach; 1 Steven Kitshoff, 2 Bongi Mbonambi, 3 Frans Malherbe, 4 Eben Etzebeth, 5 Lood de Jager, 6 Siya Kolisi (c), 7 Franco Mostert, 8 Jasper Wiese.

Replacements: 16 Malcolm Marx, 17 Trevor Nyakane, 18 Vincent Koch, 19 Marco van Staden, 20 Kwagga Smith, 21 Herschel Jantjies, 22 Morne Steyn, 23 Damian Willemse.

Follow South Africa v Lions third Test with our live blog on RTÉ.ie/sport and the RTÉ News app or listen to live commentary with Donal Lenihan and Michael Corcoran on RTÉ's 2fm from 4.45pm Saturday.