There were certainly a few scoffs when Martin Tyler suggested that the 3-2 win over Spain in Betis was a greater achievement for England than reaching the semi-finals of the World Cup for only the third time in their history. But if we expand the Sky Sports commentator's argument to England's Nations League campaign in its entirety, and perhaps he has a point.

While the World Cup provided the foundations of positivity to build the subsequent progress under Gareth Southgate upon, a competition few had heard of let alone understood before a ball was kicked at Russia 2018 has had a transformative impact on this Three Lions side, the legacy of which could prove far further reaching than England's exploits during the summer.

Let's clear something up; the idea that England were fortunate to reach the semi-finals is pure fallacy. It's a fantastic achievement from a nation of serial underachievers because even if you believe England should have beaten every team they met up until Croatia, as the bookies and FIFA rankings dictated, the Three Lions spectacularly imploded under the pressure of being heavy favourites just two years ago at Euro 2016, crumbling against Iceland in the first knockout round.

Harry Kane celebrates scoring against Croatia

So lowly had England fallen that merely beating the teams they're supposed to beat, while employing a moderately exciting and technically-demanding brand of football, was a massive step forward for the Three Lions both tactically and psychologically.

Perhaps the greatest indicator of that was the 6-1 victory over Panama - probably the least qualified team at the tournament, yet one England ripped apart in style to record their biggest ever World Cup win. Compare that to 2014 and 2010, when the Three Lions failed to score against Costa Rica and Algeria respectively.

The other watershed moment was of course the penalty shootout against Colombia, lifting a curse at international tournaments that had persisted since England's only other penalty shootout victory back at Euro 96. But just like the demolition of Panama, the penalty shootout didn't really tell us anything new about this England team or particularly take it to greater horizons.

It expelled demons but we've always known England have the talent to thrash smaller nations like Panama and we've always known they're capable of winning a penalty shootout - only a mental block, always shackling England to the failings of prior generations, really stood in the way.

Southgate deserves immense credit for that - it required a seismic psychological shift amongst the England camp in an incredibly short space of time, while still relying on many of the same young players that Roy Hodgson took to his final major tournament.

But it's throughout the Nations League where England have really grown, and proved that they're not only capable of handling the pressure to meet expectations but also exceed them to move into the top calibre of international sides. For starters, when was the last time England beat two members of FIFA's top ten in back-to-back competitive games? Has it actually ever happened before?

Eric Dier yells at Sergio Ramos

Along the way, there were more transformative moments in the Nations League campaign than during the World Cup, the first and most significant of those coming in the first encounter with semi-final nemeses Croatia. It was a drab game further hindered by the ghostly atmosphere of the behind-closed-doors ruling, but one that nonetheless highlighted a tactical awareness Southgate and England seemed to lack during the summer.

In Russia, 3-1-4-2 was stuck to religiously to the point that it became England's ultimate undoing and subsequently cost them a defeat to Spain on the Nations League's opening weekend, but Southgate refused to be fooled twice and cancelled out Croatia's quality in midfield by matching up with their 4-3-3.

It gave England a Plan B, proved their World Cup progress was by no means due to capturing one moment of tactical zeitgeist alone and laid out  along-term system to build future squads around. Most importantly though, the performance confirmed England are capable of matching opposition of World Cup finalist calibre.

The victory over Spain of course showed signs of further growth and the whole ninety minutes was another key moment for this England team, ending a run of 38 home games without defeat for Luis Enrique's side. The last time England beat a truly top team in their own back yard in a competitive fixture was the 5-1 against Germany, all the way back in 2001.

Gareth Southgate gives instructions

But within it was another, even more crucial incident for the development and longevity of this England team; alongside the prior implementation of 4-3-3, during the game itself England changed to a back five to hold onto the lead and handled the switch immaculately. In the space of 180 minutes then, England had gone from only operating within the confines of 3-1-4-2 to switching to 4-3-3 and then modifying it during a match. It required exceptional organising and implementation from Southgate, but also tactical awareness and adaptability from his players too.

And then against Croatia at home came another watershed moment of Southgate's spell in charge. England's run of failing to score a goal after making their first substitution spanned all the way back to the start of the World Cup, but it was Manchester United's Jesse Lingard who netted from the bench to draw the Three Lions level on Sunday with just twelve minutes left on the clock.

Fellow substitutes Dele Alli and Jadon Sancho had a positive impact too, as England won a game after being behind in the final 15 minutes for the first time in their history - a run spanning 601 competitive fixtures.

Jesse Lingard pokes home against Croatia

Indeed, while the World Cup campaign restored England to where they should be, the Nations League has pushed the Three Lions to a higher level; one where they cancel out world-class midfields, change games from the bench, launch last-minute comebacks and employ a variety of formations. The squad has jumped up a level too.

Whereas there was an obvious first and second string in Russia, every player in every position - with the exception of Harry Kane and Jordan Pickford - now finds himself under threat of genuine competition for a starting role. Suddenly, Southgate has a whole raft of talented young players to call upon.

And the Nations League effect doesn't have to stop there either; should England win their ultimate two games after qualifying for the final four, they'll achieve a first for the Three Lions since 1966 - lift an international trophy.

Representing yet another gigantic leap for this England team, one that will no doubt help it at Euro 2020 and the next World Cup, that would complete the legacy of a Nations League campaign that is already far exceeding the ramifications of Russia 2018.

Check out Playmaker FC's Tom Skinner's unfiltered take on Wayne Rooney's England legacy in the video below...