The World Cup might never open up again this way for this generation of English footballers, or perhaps it is just too early to draw those conclusions after a month in which we have seen the scope of what is possible change in front of our eyes.
Even so, England were dominant in the first half and then gradually pushed back by the will of a Croatia team driven on by Luka Modric who adjusted to the challenges with all the shrewdness that you might expect.
He will have known that there were chances for England, in the lead after four minutes through Kieran Trippier, to kill Croatia’s dream before the referee blew for half-time – and that England had failed to take them.
Mandzukic’s goal, poached in the fourth minute of the second period of extra-time, was that tiny margin that decides careers – a header lost by Trippier to Ivan Perisic, who had scored the equaliser, and then the Juventus striker lashing a shot past Jordan Pickford.
England sent on Marcus Rashford and then later Jamie Vardy but they could not recreate the chances that had passed them by in such a bright and confident first half. It has been a tournament that has opened the eyes to what is possible – penalty shoot-out victories, a good young England team playing a bold new formation.
But this night also demonstrated how much it takes to win a tournament like this, how every game is a separate battle that must be won in its own way, and this one slipped away from England as they were gradually denied the ball and the rhythm of their start in the game.
If there was a regret at half-time then it was that England led by just the single goal because there were times when you thought that they might have broken their opposition for good in a flurry of two or three goals – the chances were certainly there.
The Croatians had hung on for that first half to stay in the game, although there were times when they had little control over the outcome and just had to hope that England would blow it on their behalf.
Jesse Lingard was presented with the ball on the edge of the area on 36 minutes and even had the time to take a touch before stroking his shot wide of the post when he had so much of the goal to aim at.
Danijel Subasic, the Croatia goalkeeper, had come to to his team’s rescue a few minutes earlier when Lingard played in Harry Kane and the striker missed with both of the opportunities that were presented to him.
First when Subasic got something on the ball from the first shot and then when the England captain tried to force the ball in from close and clipped the post. Even so, it was hard to fault that first half from England tactically.
They had slightly less of the ball but they gave Croatia’s midfield barely space to breathe. In that area, Modric found himself surrounded by a well-drilled core of Dele Alli, Lingard and Jordan Henderson, who closed in on him whenever the ball was attracted to that part of the pitch.
Barely a decision went Croatia’s way – unless you count the lenience of referee Cuneyt Cakir towards Dejan Lovren, and really you should – and when there was the chance of a pass going astray then it did. Just before the Kane chance, the left-back Ivan Strinic passed the ball straight into touch on the left side and his manager Zlatko Dalic allowed his despair to show itself for a second before composing himself.
The goal had come early, from a premium free-kick conceded by Modric of all people who clipped the heels of Dele. Even then at that early stage, England had worked it well from Lingard’s tidy knockdown and suddenly there was a great chance, on the edge of the box and central.
Trippier stroked it over the wall and past Subasic’s right hand like he was clearing the last ball in the garden through an invitingly open garden shed door.
This was confidence and it electrified England. Raheem Sterling ran the defence of Lovren and Domagoj Vida, the latter of whom was booed by the Russian crowd for every touch – a legacy of his pro-Ukraine remark. It was in the carefulness of England’s defending that the changes in this team were clear.
At the end of the half, Kyle Walker matched Ivan Rakitic step for step in the area when a flat clearance from Jordan Pickford was returned quickly. Jordan Henderson got a foot to Modric’s shot. There was no margin for error. There was purpose from Croatia from the beginning of the second half and they seemed more liberated knowing that it was now or never.
As the game went into the final ten minutes, England’s share of possession after half-time had dropped to 30 per cent. They were being pressed much higher up the pitch by Croatia and although there was space in behind, Southgate’s players could not find it.
Yet still the half-chances fell to England, a knockdown from Kane to Sterling that Lingard took on the full and was blocked by Lovren. Sterling, later to be replaced by Marcus Rashford after the equaliser, stumbled with the ball at his feet in the Croatia area.
Kane had a shot from a difficult angle from the right, off target. As the risks grew so too the chances of a mistake. Yet when Sime Vrsaljko picked the ball up on the right and whipped in a cross on 68 minutes it felt like the kind that England had dealt with all night.
Walker dived for it and with the ball at shoulder height, Perisic jabbed a foot in above the head of the defender and steered it past Pickford.
There were no major protests from the English side even if the foot felt suspiciously high. Almost immediately Croatia surged forward, Perisic’s shot hit the post and came out to Rebic.
This felt like the moment of the game so far – and he hit his shot straight at Pickford. Just on the brink of extra-time, Trippier picked out Kane with a free-kick and he headed wide. When Mandzukic struck in extra-time, the door was shut on England.