Cape Town - The upgrade in size is no coincidence. South Africa head coach Allister Coetzee knows that to win at Twickenham, his side must control the ball.
Tendai Mtawarira is the only survivor up front from last weekend's draw against the Barbarians as the Boks go big in the tight five and back-row.
Answering their injury problems at openside flanker by moving Pieter-Steph du Toit from lock to seven, and bringing in Lood de Jager to partner Eben Etzebeth, makes a statement. Willem Alberts, returning on the other flank, isn't exactly known for his subtle approach.
Measure up the weight of the two packs, and in fact it is England who are the heavier by a solitary kilogramme. South Africa's pack might be big, but it also needs to be.
Saturday's forecast too had a role to play in Coetzee's selection with Twickenham set for rain and no lack of wind either.
“I have selected the best possible team that can supply us with that possession and offer the team go forward. In conditions like Saturday go forward is important - it will be the battle of the gain-line as well," Coetzee said.
"This game cannot be played without any form of physicality or any form of gain-line dominance. You have to earn that and this pack of forwards that we have selected suits the game we want to play.
"The back-row was always going to be a tough challenge with all the injuries that have been pointed out before. As an openside, Pieter-Steph du Toit has played throughout the season exceptionally well. He has a phenomenal work-rate - it gives us another opportunity at lineout time. He runs good lines as a ball carrier as well and is suited to that role.
"Warren Whiteley is the link between backs and forwards and he’s got the legs to run around the field. Willem Alberts is an experienced Test player who has been to Twickenham before.
"We have a lot of youngsters out there that could have done that job, maybe. But you have to make sure you expose players, especially young players, in their Test career at the right time.
"We have to make sure we respect the conditions. It will be a proper Test match and it will most likely start up front. Tests are about set-piece and territory. You can’t get territory if you can’t get your set-piece in the right area. That’s where it will be."
Given the heat Coetzee is already under months into his new role, you expect he is praying for a revival similar to the one produced by England over the last 12 months.
Both last week before facing the Barbarians and again on Thursday he emphasised the importance of Stuart Lancaster's work in exposing a number of England's top players today to international rugby, stressing the need for a long-term vision despite patience back in South Africa being short.
Back to the present and flaws in England's defence have been recognised, as has the fact that they rarely concede tries - 17.6 points per game thus far to be exact, with bragging rights over an old friend are also at stake for Coetzee.
"England have got a solid defence system in place. They have worked hard at it. You see a lot of line-breaks but you do not see a lot of tries scored against them. They do something right in terms of how they scramble and shut down teams. We are well aware of that," Coetzee explained.
"I think we need to have a good balance in the way we want to play. I am really happy with where we are in our plan and getting that balance right between asking questions with ball in hand and having to turn the opposition or kick the ball.
"It is a very good team. Although you also mention injuries to the lock pairing of (Maro) Itoje and (George) Kruis, but you look at (Courtney) Lawes and (Joe) Launchbury with (Dave) Attwood on the bench, it is still a classy team. It is also a team that has been together for the Six Nations and during the tour of Australia so there is a lot of continuity.
"This is what our players are really looking forward to playing against the second best team in world rugby today. This weekend they would like to measure themselves against these players. There’s a lot of talk around the physicality and a lot of talk about a lot of things but come Saturday you have to prove that.
"Eddie is a flipping hard working coach. The guy does not leave any stone unturned. He’s thorough and he’s a competitive man.
"He will never disrespect South Africa, he will never take us lightly irrespective of our Rugby Championship that we have had. He’s a genuine rugby man and a good man."
15 Mike Brown, 14 Marland Yarde, 13 Elliot Daly, 12 Owen Farrell, 11 Jonny May, 10 George Ford, 9 Ben Youngs, 8 Billy Vunipola, 7 Tom Wood, 6 Chris Robshaw, 5 Courtney Lawes, 4 Joe Launchbury, 3 Dan Cole, 2 Dylan Hartley (captain), 1 Mako Vunipola
Substitutes: 16 Jamie George, 17 Joe Marler, 18 Kyle Sinckler, 19 Dave Attwood, 20 Nathan Hughes, 21 Danny Care, 22 Ben Te'o, 23 Jonathan Joseph
15 Willie le Roux, 14 Ruan Combrinck, 13 Francois Venter, 12 Damian de Allende, 11 JP Pietersen, 10 Pat Lambie, 9 Rudy Paige, 8 Warren Whiteley, 7 Pieter-Steph du Toit, 6 Willem Alberts, 5 Lood de Jager, 4 Eben Etzebeth, 3 Vincent Koch, 2 Adriaan Strauss (captain), 1 Tendai Mtawarira
Substitutes: 16 Bongi Mbonambi, 17 Steven Kitshoff, 18 Lourens Adriaanse, 19, Franco Mostert, 20, Nizaam Carr, 21, Faf de Klerk, 22, Johan Goosen, 23 Lionel Mapoe