Trent Alexander-Arnold will not participate in the Euro 2020 tournament after picking up a thigh injury in the friendly win over Austria.
The Liverpool defender limped out of Wednesday’s 1-0 win and has now been ruled out for up to six weeks.
After the scan, he was told to rest for at least a month.
Southgate has defenders Ben White and Ben Godfrey ready and waiting after the pair were cut from England’s final 26-man squad.
Jesse Lingard and James Ward-Prowse are also options.
Gareth Southgate will not confirm a replacement until after Sunday’s game against Romania