Southgate has to let the shackles off, it will be interesting to see his line up.
Southgate is looking to wing-back options, and among those is Bukayo Saka who stepped in as an emergency left-back against Slovakia due to Trippier's injury.
Saka has not regularly featured in a defensive role for club or country in several seasons, but he can play there and it may be a case of needs must.
The right wing-back may be Trippier, or Trent Alexander-Arnold could feature there in a more familiar role following Southgate's failed midfield experiment with the Liverpool man at the start of the tournament.
Any switch of formation would also affect England in advanced positions. Should England play 3-4-2-1, it would probably see Bellingham and Phil Foden employed as dual number 10s behind Harry Kane.
Foden has been played on the left so far at Euro 2024 and his propensity to drift inside into areas already occupied by Bellingham has caused England issues.
The width instead being covered by wing-backs could solve that problem.
A back three would potentially also allow England to more easily play two strikers, as they did late on against Slovakia to good effect – substitute Ivan Toney assisting Kane's extra-time winner.
The final reason we are likely to see a back three is to match up against a Swiss side who have been among the most impressive at Euro 2024.
Switzerland caught the eye when holding hosts Germany in their final group game – only denied a win and top spot in Group A by a late Niclas Fullkrug equaliser – and handily beat defending champions Italy 2-0 in the round of 16.
Hakan Yakin's side play a back three, so Southgate may aim to go toe to toe.
The last time England 'matched' a top European side's starting formation with three at the back was in a 1-0 Nations League loss in Italy in September 2022.
But having only survived at Euro 2024 by the skin of their teeth, England know they must try something new – or a new variation on an old favourite.
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