South Africa forwards coach Matt Proudfoot hopes his side can channel Ireland's game plan as they look to overcome the odds against England.
The Irish ended New Zealand's 18-game winning streak in Chicago over the weekend and, even though South Africa are unbeaten against England in 10 years, the teams will run out at Twickenham on Saturday in very different form.
England are unbeaten in nine Tests since Eddie Jones took over, and 10 games in total, while the Springboks arrive after a disappointing two wins from six games in the Rugby Championship and a 31-31 draw with the Barbarians at Wembley.
But Proudfoot, asked whether Ireland have proved anyone is beatable, said: "Correct and I think the key there is the Irish had a very sound plan and executed it very well.
"Their line-speed was tremendous and they took the All Blacks on where the All Blacks wanted to play, and nullified them as well.
"I thought the kicking game of the half-backs was exceptional as well, and that forced the All Blacks to play from very deep.
"And just the intensity of the Irish side is what you've got to have in Test match rugby.
"You hear every week 'we've got to turn up', it's a common cliche thrown about but that is the epitome of Test match rugby. If you turn up with that intensity that's right there, then yes you can beat anybody."
Proudfoot was not surprised by Ireland's 40-29 win at Soldier Field and expects them to kick on from the historic success.
"We know how tough they were in June, particularly around their defensive alignment, their defensive breakdown and how they tend to smother you," he added.
"We knew how difficult it was to crack them. By hook or crook we got away with it in June - being at home, being at altitude maybe gave us a bit of an advantage but we knew how tough they were.
"So we're not surprised. I listened to the comments of (All Blacks head coach) Steve Hansen afterwards and I echo them. He was complimentary of what Ireland are doing, and that's what you get when you get that alignment.
"If you've got 23 players who are all seeing the same picture on the field and executing that, that's when you get a great result. And that's what the Irish did.
"So they've been setting up for that victory for a long time and planning for it and processing for it. And they're a damn good side."