Gareth Southgate is considering a switch to a back-three for Saturday's Euro 2024 quarter-final against Switzerland.
England have started with a back-four throughout the tournament, but changed to a three during the second half of last weekend's dramatic last-16 win over Slovakia.
Southgate has been experimenting in training this week by trialling a wing-back system and could make the move to match up against the Swiss, who have played a 3-4-2-1 formation for most of their campaign.
Southgate used a back-three in his first tournament in charge, the 2018 World Cup in Russia, and on several occasions at Euro 2020, including in the last-16 win over Germany and the final defeat to Italy.
Here, England have struggled for width on the left flank in each of their four matches, with the right-footed Kieran Trippier deputising at left-back for the injured Luke Shaw and Phil Foden not a natural wide player.
Shaw is back in training and in contention to feature against the Swiss, but it is unlikely Southgate will risk the Manchester United defender from the start after almost five months on the sidelines with a hamstring problem.
However, Arsenal star Bukayo Saka offers another left-footed option on that flank.
The 22-year-old made his Gunners breakthrough as a wing-back as a teenager, and while he suggested last week that shifting him from what is now his established post on the right of attack was "not the solution" to England's problems, Southgate opted to do so as his side chased the game at 1-0 down against Slovakia.
One change the Three Lions boss will definitely have to make is at centre-back, where Crystal Palace's Marc Guehi is suspended. Aston Villa's Ezri Konsa expected to come into the side in his place.
