Tuesday's result followed the Three Lions' goalless draw with world champions Germany on Friday.
"I thought they were all excellent," Southgate told reporters. "Joe [Gomez] has been given the man-of-the-match award and rightly so.
"In the two games, I think John Stones has really shown his defensive attributes. He's looked really mature, controlled the line and taken pride in his defending as well as being calm in possession.
"Harry [Maguire] has also been a real plus. He started a little anxiously today but he grew in confidence and grew into the game."
The England defenders return to Premier League action this weekend, with Liverpool, Leicester City and Manchester City all in action on Saturday.