Ask South Africa’s players and they could scarcely be more complimentary. “He’s an unbelievable coach,” the Springboks’ full-back Willie le Roux says. “It’s a privilege to work with him.” His teammate Kwagga Smith feels similarly. “He’s an amazing coach and person. All of us as Springboks are better players because of him.”

Interestingly the man to whom they are referring is neither Rassie Erasmus nor Jacques Nienaber but the 36-year-old Felix Jones, who will be switching camps to join England’s management team after this World Cup. Jones – no relation to Eddie – is not necessarily a household name across his native Ireland but if South Africa beat New Zealand at the Stade de France on Saturday his coaching CV will feature two World Cup final victories plus a series victory over the British & Irish Lions in 2021.

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Small wonder Steve Borthwick was so keen to add him to his England brains trust, with Kevin Sinfield poised to depart after the World Cup. Jones will not confirm the specific role he will be taking with England but his work ethic is definitely in no doubt. “I don’t think I’ve ever seen him without his laptop,” Le Roux says. “He helps us with our attack, our strike moves, the backs … I think the Springboks are really going to miss him.”

As recently as 2015 Jones was still a back three player with Munster and Ireland, for whom he won full 13 caps. A neck injury forced him into retirement at the age of 28, however, since when he has swiftly carved out a reputation as a modern-thinking coach with a keen eye for detail. “He just looks so much into the small details,” says Smith. “You always think you’ve got a good pass until he puts footage up and says ‘Listen, this is how you do it’.”

Watchful and intelligent, Jones hails from Dublin originally but it was in Munster where he had his eyes opened to different ways of looking at rugby. He cites the New Zealander Rodd Penney as an important influence – “He changed the way I thought about the game” – but it was the relationship he struck up with Erasmus and Nienaber during their spell with Munster between 2016 and 2017 that really turbo-charged his coaching career.

Fast forward to last Saturday and all three were confronted by the trickiest challenges imaginable. England were ahead on the scoreboard and dominating the game, only to be outfoxed by South Africa’s substitution strategy, scrummaging excellence and collective belief. Jones openly admits working with Erasmus and Nienaber has been an educational experience. “They think about things differently to what you’d expect. [Often] it’s another point of view that, in most cases, most people won’t have considered. Everything gets discussed, everyone makes a plan and we align on that. If we agree then great. If someone disagrees and we have a better plan then we go with that. It’s always enjoyable.”

Juggling the demands of a young family with his role with the Springboks has not always been logistically easy but victory this weekend would help to make such sacrifices worthwhile. He will also forever be grateful to South African rugby for making him reconsider some aspects of the game. “There are certain parts that have definitely changed my view. Collision winning, for example, is actually a skill. I think sometimes that can be considered as just people hitting things but actually there is a huge amount that goes into it.”

The more immediate challenge, having seen his side perform “a jail break” against England to quote the ex-South African captain John Smit, is to rise to this weekend’s big occasion. The Springboks will confirm their starting XV on Thursday and Jones has no concerns about the hooker, Bongi Mbonambi, who has already played 160 minutes of demanding knockout rugby. “He has come through both of those games fine. I think any player that’s getting ready to play in a World Cup final won’t moan about how many minutes they’ve had. They’ll be ready to go.”

Le Roux, meanwhile, insisted there was no malice in his post-game celebrations which briefly upset some English players last Saturday. “I jumped up out of happiness as we’d just got through a World Cup semi-final. There was no disrespect to any of the English players. I think they thought there was [but] I immediately told them there wasn’t and then it stopped.”