Sunday 10 June 2018 23:59, UK
South Africa's Faf de Klerk says altitude played a massive part in the Springboks beating England who were vulnerable because they decided to train at sea level.
De Klerk was the ringmaster as Eddie Jones' men slumped to a fourth successive Test defeat by allowing a 21-point lead established inside the opening quarter to slide into a 42-39 loss.
Jones has located his squad in Umhlanga by the Indian Ocean rather than on the Highveld even though the first and second Tests are staged at altitude and established protocol dictates teams should arrive at least 10 days earlier or less than 24 hours before kick-off.
England had the scope to accommodate both of those time frames in their schedule and De Klerk has revealed their choice of training venue was noted with interest by the Springboks.
"We knew they were based in Durban and that coming from the UK the altitude was going to be a factor," De Klerk said.
"I think the altitude plays a part. England made a few errors they don't usually make and that played into our hands."
Hooker Jamie George admits that the thin air at the sport's highest venue which stands over a mile above sea level took its toll on the players, who face a similar challenge to their conditioning in Bloemfontein on Saturday.
"It was tough after 20 minutes. It really did kick in. After 20 to 30 minutes it definitely hit us quite hard," George said.
"At the same time, we'd had good plans in place from a strength and conditioning point of view. We probably need to get better at that.
"We are still at altitude in Bloemfontein, although not quite as high. We'll look to learn our lessons."
Jones remains satisfied with his plan despite a defeat in Johannesburg that has increased the pressure on his stewardship following a fifth-place finish in the recent NatWest 6 Nations.
"We don't think the benefits of staying at altitude are massive enough. And we didn't lose the game because of altitude," he said.
"The way we started the game and thereafter, you wouldn't have thought altitude was the problem. It was a momentum game based on possession."
An indicator of the tension that has set in amid England's slump was Jones' response when pushed on their recent form.
Including last month's nine-try rout by the Barbarians at Twickenham, the run stands at five losses but Jones is eager to scrub the non-cap international from the record books.
"We've not had five defeats. We have lost four Test matches," he said.
When pressed on the sequence, Jones replied: "I'm not going to answer that question because I will lose my patience."
Will England bounce back in the second Test? Tune into Sky Sports Action and Main Event from 3pm on Saturday June 16 to follow the Rose on England's journey to the 2019 Rugby World Cup