The Crystal Palace defender was making his first start for England at a major tournament, and excelled alongside John Stones as the Three Lions claimed a clean sheet and all three points against Serbia.
“I saw the player that plays every week for his club,” Southgate said in his post-match press conference.
“He is positionally sound, calm. Tonight was an even bigger test because stature-wise he is not one of the bigger centre-backs, and there was going to be a lot of aerial balls into the box, which he dealt with well.
“I thought he transferred what he does for his club onto the biggest stage, and showed what a good player he is.”
Presenting the BBC coverage, England legend Gary Lineker was just as impressed – not just with Guéhi’s performance on the pitch, but with his character off it.
“What a delightful young man,” he said. “So modest, but so impressive. I have liked him for a long time.”
Rio Ferdinand, one of England’s standout defenders of the modern era, added his praise to Lineker’s.
“Positionally on the front foot, cool, calm and collected,” he explained. “He doesn’t want to be a superstar, he is a very humble young man.
“At 23-years-old, he [often] captains Crystal Palace, a Premier League team. He doesn’t look like he is going to be phased.
“I don’t like emotional defenders, and he’s not one of those.”
Micah Richards praised the simplicity of Guéhi’s game, avoiding the kind of over-complication which can lead a team into trouble at the back, while retaining his ability to play his way out of danger.
“[He is] a joy to watch,” Richards said. “He is very calm – obviously going to the Euros must be daunting at times. He didn’t show that in the game at all.
“The thing I liked about him today was that he did the basics very well. He didn’t try to do anything out of the ordinary.
“As a centre-half you just want to be solid, and whether it was getting tight, whether it was playing out, anticipation, he was always on the front foot and ready.”