Foden did not start either of England's first two games of the World Cup and was an unused substitute in the goalless draw with the USA on Friday, leading pundits and fans questioning Southgate's decision not to turn to one of the Premier League's most talented young players.
The 22-year-old Manchester City playmaker will be hoping to start Tuesday's final group game against Wales but Southgate has played down his chances of playing centrally, and warned against putting too pressure on his shoulders.
"Sometimes the discussion around just plopping him in as a 10 in every game isn’t realistic because in a game like the other night you have to have the ball and there are defensive responsibilities that he doesn’t have to do at his club," Southgate said.
"There are games where there isn’t that same tactical challenge in midfield. There might be a little bit more freedom and that might be the slot he can go and express himself. But his club don’t do that, so there must be a reason for that.
"But he’s a great option for us in two or three different positions and he will have a big impact in games. But also we have to be careful because we are putting a lot of pressure on him now. We’re a team and we need all of the players and they can all play a part but not any one of them is the reason we will win or lose.
"And we need to make sure we are not building Phil into a situation where actually if he steps on the pitch this is becoming really difficult for him because the level of expectation is beyond a young guy who is still establishing himself internationally, in a different environment from his club where you’re comfortable with all the players you play with.
England Training Session for FIFA World Cup 2022 Qatar | 28th November 2022
"[At club level] it's really distinctive, you’re going home every night, you’re calm with everything else. This is still a unique environment. He is still a really young player and he’s doing brilliantly well and we love him to bits. We also have got to look after him a bit as well."
Jack Grealish and Marcus Rashford both came off the bench against the US, having scored as substitutes in the 6-2 thrashing of Iran.
At last summer's European Championship, fans were clamouring for Grealish to play and Southgate suggested he would always be taking flak for not playing one of his forwards.
"We have Jack who 18 months ago I was being murdered for not using," he said. "Marcus we feel has been in really good strength. Phil of course is a player we love who can change games as well. Had we put Phil on and he hadn’t scored we would have been talking about Jack, or Marcus.
"That’s a little bit where we are. I’m not going to change that. I know for a lot of people they have decided how it is and I’ve just got to keep making the decision that give us the best chance of winning.
"We have just got really good players. Bukayo [Saka] has been an outstanding player in the league this year. Raheem [Sterling] has scored 20 goals in 80 caps for England. Jack and Marcus are also in good form. We are really happy with Phil, we are really happy to have Phil. He is going to play a big part in this tournament, there is no doubt in my mind about that."
Southgate is not expected to make wholesale changes against Wales, with England still yet to technically book their place in the last-16, and top spot in Group B still at play.
Four years ago in Russia, Southgate faced criticism for making eight changes for the final group game against Belgium, with qualification already secure and he added: "I’ve sort of worked out how all of this works.
"If we change it we shouldn’t have. If we win it was justified if we don’t it wasn’t.
"We just have to make best decisions with the information we have and prepare the team in the best possible way. We want to play well. We want to win the group, we want to win football matches. There has to be a balance of freshness. Without a doubt the two games have taken a lot out of the players. But also stability. If you make lots of changes you can lose a bit of rhythm as well."