Just over 24 hours after England lost their 2018 World Cup semifinal to Croatia, manager Gareth Southgate found himself watching a replay of the game at 4 a.m. "In terms of mentality, it's obviously been a really difficult couple of days," he explained at the time. "That is going to live with me forever."

England's shot at redemption comes on Sunday in their Euro 2020 opener -- stream LIVE on ESPN, ESPN+, 9 a.m. ET (U.S. only) -- as they renew a rivalry that's also helped illustrate their progress during Southgate's five years in charge.

Croatia outclassed and outlasted England with a 2-1 win in extra-time in Moscow. England looked physically exhausted by the end of a gruelling 120 minutes, yet it was their opponents who were playing extra-time for the third consecutive game. Real Madrid midfielder Luka Modric helped Croatia control the game in midfield, with a maturity in possession England were unable to replicate.

The big question is: Will it be any different this time? And can England go all the way this summer?

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Back in 2018, there is no doubt that England benefitted from a kind draw to advance to the final four in Russia. They were able to ease into the group stage by facing Tunisia and Panama, winning both matches to render their toughest test, against Belgium, an irrelevance as both sides named weakened teams with qualification already assured.

England do not have that luxury at Euro 2020. Although facing Scotland will be a highly emotive occasion and the Czech Republic beat England in qualifying, Croatia represent the toughest Group D assignment, and England's problems against the best sides -- the thing that dooms every tournament run in the knockout stages -- long pre-date Southgate.

Croatia are ranked 14th in the world. The last time England won a tournament match against a higher-ranked team was at the 2002 World Cup, when a David Beckham penalty earned Sven Goran-Eriksson's side a 1-0 win over Argentina (then ranked No. 3 by FIFA).

There are several reasons for this, including a lack of quality, the weight of history, undue expectations, a pathological fear of penalties and a team picked on reputation rather than performance. There were hopes of a new era when England thrashed Croatia (then ranked No. 25) 4-2 at Euro 2004, as Wayne Rooney burst onto the scene, but there has been a familiar feel to most tournament exits, perhaps aside from crashing out to Iceland at Euro 2016. England were beaten by Germany in 2010, Italy on penalties at Euro 2012, exited the group stage in 2014 after losing to Italy again and Uruguay, before defeat to Croatia in the semifinal three years ago.

The inaugural Nations League gave England a quick chance for revenge, drawing 0-0 in Croatia before winning the reverse fixture 2-1 at Wembley in November 2018, a group stage which also contained a notable 3-2 win in Spain. But again they came up short, losing 3-1 to Netherlands in the semifinal.

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Modric is arguably more pivotal to Croatia than ever. Since the 2018 World Cup, Danijel Subasic, Ivan Strinic, Mario Mandzukic and Ivan Rakitic have all retired, a total of 288 caps and a wealth of experience departing with them. Mandzukic's 33 goals is a tally bettered for his country by only Davor Suker (45), while Rakitic stepped down as the fourth most-capped player in Croatia's history (106 appearances).

Rakitic's role could be filled by Mateo Kovacic, who can provide useful insight on three England players: his Chelsea teammates Mason Mount, Reece James and Ben Chilwell. But inevitably, the focus will be on the 35-year-old Modric and whether England have developed into a team capable of nullifying, and then overpowering, a player who won the Golden Ball as the tournament's best player two years ago.

"He's always been a player that I've looked up to, ever since he was in the Premier League playing for Tottenham," said the 22-year-old Mount, who swapped shirts with Modric after their two Nations League meetings.

"I watched him quite closely as a kid. And then obviously playing against him, it was weird because I watched him so much growing up, I knew his moves and what he was going to do. It helps being a fan of a player and then playing against him. The experience of that game helps a lot. As a young player, you want to play in these big games and learn how to handle the pressure, how to handle these big moments."

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Among the conundrums for Southgate is his central midfield pairing. Whether he chooses a 3-4-2-1 shape or 4-3-3, the heart of the pitch is a problem area.

Declan Rice has excelled for West Ham this season, but is unproven on this biggest of stages. Jordan Henderson has played just 45 minutes since Feb. 20 due to a groin problem and although Mount is versatile to play anywhere, it would be a bold call for Southgate to pair him with his best friend Rice, while also accommodating at least two more attacking midfielders in support of Harry Kane. Leeds' Kalvin Phillips is more defensive minded, but has just eight caps to his name.

With Henderson's fitness in doubt, as well as that of centre-back Harry Maguire, and players joining up on a staggered basis following Manchester United, Chelsea and Manchester City's involvement in the major European finals at club level, England's preparations have endured an unwanted degree of turbulence. Yet the serenity of St George's Park has brought a sense of calm. England's players have engaged with the media this week in the same transparent approach as Russia -- COVID protocols notwithstanding -- reviving the daily darts match and often sitting in on each other's news conferences to observe the interactions.

Upon their arrival at SGP, Southgate showed the players a video that underlined why this summer is an opportunity to embrace, rather than a potential failure to be feared. The coaching staff have been keen not to overload the players, too, allowing them downtime for playing basketball, table tennis and pool, or enjoying meals on the outdoor terrace with the British summer weather arriving on cue.

The players arrived in their hotel rooms to find photos of their loved ones, another touch reproduced from their time in Russia. Aston Villa midfielder Jack Grealish was particularly delighted with the picture of his dog. Yet one thing they cannot replicate from three years ago is the low expectations.

England thrived at Russia 2018 with an atmosphere free of the usual hyperbole, taking advantage of a desirable draw to reach the semifinals. They have neither to aid them this time, particularly given France, Germany or Portugal await in the round of 16 if they win Group D.

England have the second-youngest squad but are still second favourites with most bookmakers, and a country only recently released from near-total lockdown is ready to embrace the closest thing it has had to a home tournament for 25 years.

Southgate has decisions to make, choosing from a talented squad brimming with attacking threat. With that, inevitably, comes expectation. And appropriately enough, the first test of their prospects comes against the team that ended their "summer of love" in 2018.

"That was a massive disappointment, a big blow at the time," United defender Luke Shaw told ESPN. "[England] did very well to get to the semis but it is always going to be a low if you get knocked out there. There's extra determination to go one step further this time, and what a game to start with against Croatia."

Mount added: "If you look at the amount of talent going forward, it speaks for itself. We've got players who can handle the ball, keep the ball, play possession football, create chances and be a threat going forward.

"There will be times when things don't click, but with the players we have and what we've been working on in training, I have full hope it is going to work, we are going to play together and it is going to connect."