It is unclear who will drop out but Gallagher’s place seems uncertain given the 24-year-old’s lack of impact against Slovenia. The former Crystal Palace loanee is also carrying a yellow card after being booked against Denmark.
There has been clamour for Mainoo or Palace’s 20-year-old midfielder Adam Wharton to be given game time. Some fans and pundits have also wondered whether a change in formation might help Southgate get the best out of his underperforming team.
The 53-year-old, who guided England to the final of Euro 2020, was targeted by empty beer cups from dissenting fans after the draw with Slovenia in Cologne. However, defender Marc Guehi has defended Southgate.
“He has been fantastic for England. If you look at his record, it speaks for itself,” Guehi said in Thursday’s press conference.
“Everyone is behind the manager and we have a really close tight-knit group just focused on the next group. Everyone appreciates him, especially me.
“He gave me my debut for England and he’s showed so much confidence in me. I am really grateful and I’m sure the rest of the team is as well.”
England finished top of Group C in spite of some underwhelming performances. They beat Serbia 1-0 in Gelsenkirchen in their opening game before being held to a 1-1 stalemate by Denmark in Frankfurt.
Mainoo enjoyed an excellent breakthrough campaign with Man Utd and scored in their FA Cup final triumph over rivals Manchester City.