The Three Lions manager has sported a navy blue Marks & Spencer one throughout England's run to the World Cup semi-finals in Russian Federation, which has led to increased sales and more Google searches for the item back home.
One defeat against a second-rate Belgium XI has tarnished an otherwise flawless record for Southgate's side, while England have avoided perennial powerhouses Spain, Germany and Brazil.
Though Dier would dearly loved to have given those supporters a World Cup final, he remains proud of England's efforts.
Eric Amsalem, a 48-year-old Croatian fan with his face painted in the colours of the national flag said: "It's a small country".
As expected, tonight's match proved to be an entertaining one for the neutrals and a stressful experience for English supporters, who have always been claiming that this is the year it finally comes home again.
If England is to advance, it will have to get through Croatia, which has its own history of World Cup futility.
"He was carrying something in the second half against Colombia, he wasn't moving around.
So I chose to build a pub", Lewis said. "That makes me proud".
In their other appearance, in 1966, in London, they entered popular folklore by beating West Germany, an achievement that many fans have long thought they would never see again.
"Extra time, I knew it was on the cards we weren't going to win that".
"We went through a lot of s**t", he said.
Croatia beat Russian Federation on penalties in Sochi on July 8 to book a spot in the World Cup semi-finals, while England outclassed Sweden 2-0 the day before Croatia's victory.
That year, France both hosted FIFA's World Cup and won, beating Brazil 3-0. You don't get that reaction if you haven't played as well as you have.
"Maybe [that was] a outcome of being ahead and being the least experienced team in the tournament with the chance to get to a World Cup final", he added.
"The first half was not good for us".