Marc Guehi had made just 11 appearances before the tournament.Photograph: Alex Gottschalk/DeFodi Images/REX/Shutterstock Nothing can prepare a defender for it; the demands and the pressure, the intensity, the sheer remorselessness. They might have heard the stories, especially at major tournaments. But until they have done it, they do not know. Yes, playing in front of the England goalkeeper, Jordan Pickford, is certainly something else.

"It's just the amount of talking," the centre-half Marc Guehi says with a smile. "It is a lot but it is good. I would say I am not particularly used to Jordan and it is a bit of a shock at first. But when you look at it, he is fantastic. It's constant communication, constantly making sure you are staying alert and his clean sheet record speaks for itself."

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There has been an awful lot for Guehi to take on at Euro 2024. Aged 23 and capped 11 times before the tournament, he was the relatively untested element for Gareth Southgate at the back, stepping on to the grand stage for the first time.

Around him were the stalwarts - not just Pickford but Kyle Walker and Kieran Trippier at full-back, John Stones in the middle; all great friends, the bonds forged in the heat of England's most high-profile games in recent years. They were missing one of their number - the injured Harry Maguire, whose big boots Guehi had to fill. Would the foundations remain sound?

Because, let us not forget, there were doubts, mainly individual and probably starting with Guehi, but they added up to a collective question mark. If there had been a reassuring familiarity about Stones and Maguire, a deep understanding, the same could not be said of Stones and Guehi.

Before they came to Germany, they had played together twice - in the notorious 4-0 Molineux mauling against Hungary in June 2022 and, on the eve of this tournament, the 1-0 Wembley loss to Iceland. In the latter, Guehi looked rusty, which was understandable. He had returned to the Crystal Palace starting XI only on the final day of the Premier League season after a three-month knee injury lay-off. Was it all going to be too much for him?

Stones had picked up a slight injury against Iceland and he was coming off an uneven season for Manchester City. Ditto Trippier at Newcastle; he had also just come back from a lengthy injury absence. Moreover, he would have to play on his wrong side at left-back, unbalancing the team, as Southgate waited for Luke Shaw to recover fitness after injury.

As England reflect on a bruising group stage - one that did yield qualification on top of the section - and look forward to Sunday's last-16 tie against Slovakia, the pre-tournament narrative has been turned upside down. Southgate has a defence to be respected.

It has not been completely smooth sailing. Take Guehi, for example. There have been a few errors. He was dispossessed in game two by the Denmark substitute Alexander Bah, although he would race back to make a saving tackle. In game three against Slovenia, Guehi got into a mix-up with Stones and ended up having to take a yellow card for a foul on Andraz Sporar. Will better teams in the knockout rounds punish him? The question of making do with Trippier on the left, meanwhile, has continued to burn.

Yet as a defensive unit, the numbers speak for themselves, the most persuasive one from Opta showing an expected goals against of 1.15, comfortably the best in the competition. Next on the list are Germany with 1.80. England's expected goals per shot faced is 0.04 - again, the meanest of all the competing nations.

Pickford has kept clean sheets in two of the three ties, conceding once - from distance to Denmark's Morten Hjulmand. The goalkeeper has 11 shutouts in 22 tournament appearances, an England record.

Zero in on Guehi and one statistic jumps out - the 26 ball recoveries, which puts him joint-first in the category with Hungary's Willi Orban. Guehi has shown his power in the one-on-ones and he has unarguably been one of England's best players. All this while feeling his way back to match sharpness and essentially forging a partnership with Stones on the hoof.

"Playing with John is a dream," Guehi says. "He makes my life so much easier. He's almost like a big brother, putting his arm around you, taking care of you. He's leading it, orchestrating things and I'm just learning every single day."

Ezri Konsa, the Aston Villa defender, who has yet to play here, described England as "excellent at the back" and Guehi as "outstanding ... it's great to see from the bench".

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Guehi said he was "content" but made clear that the job was nowhere near finished. "If we are to go far in the tournament, the defence needs to be strong," he said. "It's important we carry on building and it's testament to the entire team - the press from the front, the midfielders helping us with communication."

Walker's pace on the cover is a crucial part of the blend. "But it's not just that," Guehi said. "He's not just a one-trick pony. His reading of the game is fantastic, his intelligence, his positioning. It's his tenacity, his leadership. He's a top, top professional."

Guehi speaks with a maturity beyond his years and everything is underpinned by humility; a burning desire for self-improvement, too. "I get told it every day and I tell it to myself: 'I must not be too hard on myself,'" Guehi said. "I'm very, very critical of myself. I had a brief conversation about it with the manager after one of the last games I played ... just joking around, him saying not to beat yourself up."

It is easy to assume that the guidance came after the Iceland match. Guehi has since gone from strength to strength and yet there will be no resting on laurels. Pickford will see to that.