Southgate said that England have been let down by their set-piece delivery throughout the group stage, meaning that specialists such as Phil Foden and Kieran Trippier are set to return to the starting XI.
However, Mason Mount and Ben Chilwell are set to miss out as their self-isolation period does not finish until Monday, meaning they will have little time to train with the team.
During the World Cup in 2018, England scored nine of their twelve goals from set-pieces, which was crucial in leading the team to the semi-final.
But without this set-piece threat at the Euros, England have struggled to create enough chances during Euro 2020 with only two goals in three matches so far.
Southgate said: "Our delivery hasn't been good really. There was the one against Scotland where John Stones hit the post which was bang on the money and Trippier's delivery in the first game was excellent and we haven't matched that since.
"It's quite rare for us. We have gone four or five matches without a set-piece goal and that's an area we can improve upon."
According to reports, England will alter their formation to match Germany's use of a back three, which will put Jack Grealish's place in the starting line-up at risk, despite being one of the better performers in England's 1-0 win over the Czech Republic.
One guaranteed starter for Southgate on Tuesday will be Jordan Pickford. Despite serious doubts among pundits and fans that Pickford would be guaranteed the No 1 spot before the start of the tournament, Southgate has commented on his "excellent" and "decisive" displays.
Even though Pickford's Premier League performances with Everton were hit with mistakes, the England No 1 shirt has seemingly remained his own due to his qualities with the ball at his feet.
Southgate added: "I think he's been excellent. The last couple of months of the season, his performances have been very calm for his club.
"He has been decisive at the right moments for us and has made good decisions with the ball at his feet. You have seen the range of passing that he's got. He has dropped a few in to the front players. He has been able to play through the lines.
"He's in a really good place and he's given us a really solid start point for what has been strong defence from the whole team."
Featured Image Credit: PA
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