If Saturday was as exciting as the World Cup knockout stage gets, then surely Sunday occupies somewhere near the opposite end of the scale.

Having sat through more than two hours of watching Spain trying and failing to break Russia down, we were made to endure the tedium of Croatia and Denmark’s war of attrition in Nizhny Novgorod.

It started so brightly too, with Mathias Jørgensen firing Denmark in front after just a minute only for Mario Mandžukić to restore parity just three minutes later in a breathless start to proceedings.

But a precursor it was not as the two European nations proceeded to play out one of the least compelling matches we’ve seen in Russia (rivalled by France’s scoreless draw with, surprise surprise, Denmark).

It’s almost as if the footballing gods, hungover from yesterday’s thrill-ride, decided to suck the enjoyment back out of football. Brazil and Belgium are among the teams playing on Monday, so we’re telling ourselves that it will pick up once again.

Thankfully, there was penalty shootout drama and penalty drama before the shootout. Croatia spurned a chance to win it in extra-time as Kasper Schmeichel saved Luka Modrić‘s penalty after Jørgensen hauled down Andrej Kramarić.

Then, in the shootout, everyone did their best to miss before Barcelona star Ivan Rakitić stepped up and sent Croatia, rather fortuitously, into the last eight where they will meet hosts Russia, who dispatched Spain earlier in the day.

Here are five things we learned from the game.

Croatia far from their best

Part of what has made this World Cup so fascinating and unpredictable is the reluctance of one team to take it by the scruff of the neck.

Sure, France really turned it on against Argentina but, as yet, this tournament hasn’t produced a clear frontrunner.

Germany are gone. Argentina have packed their bags. Spain have crashed out.

It’s created a sense that one of the World Cup’s less-decorated nations have a genuine opportunity to reach the final – or even win the thing.

It’s not a stretch to say that Croatia have been the best of the lot. Having taken care of Nigeria in their Group D opener, the ease with which Croatia swatted aside Argentina seemed an emphatic declaration of their intent.

Play the way they did against Lionel Messi and co. and they could go as far as the 1998 side who reached the semi-finals in France. Hell, they could go even further this time.

But perhaps they peaked a little early. They weren’t entirely convincing in the defeat of Iceland and they stank the place out against Denmark.

For about 15 minutes following their equaliser in the first-half, Croatia looked genuinely threatening. As the game wore on, though, Denmark looked increasingly comfortable following a half-time tactical switch from Åge Hareide as Zlatko Dalić’s men grasped desperately for inspiration.

Christensen’s future lies in defence

Hareide’s aforementioned tactical tweak was replacing Andreas Christensen with Lasse Schøne at half-time following a difficult 45 minutes for the Chelsea man.

The 22-year-old did not feature at all in an attacking sense while he struggled defensively, his woes compounded by inadvertently gifting Mandžukić his equaliser when Henrik Dalsgaard’s attempted clearance cannoned back off his face and into the striker’s path.

Christensen’s midfield audition in the scoreless draw with France went relatively smoothly, presumably leading Hareide to conclude that he was ready for a similar assignment against Croatia.

However, France rested several stars for that group game and Croatia’s midfield technicians soon exposed Christensen’s shortcomings.

Indeed, Denmark looked considerably stronger following Schøne’s introduction. While there was certainly rationale to Hareide deploying a defensively-minded player in midfield to combat Modrić and co, it’s become clear that Christensen’s future – for both club and country – lies further back.

Perišić and Rebić offered genuine width… for about 15 minutes

Croatia are a very dangerous attacking unit and that’s thanks in no small part to the natural width provided by Ivan Perisić and Everton transfer target Ante Rebić.

Jørgensen’s night got off to a flyer when he scored after just a minute but the Huddersfield Town centre-half struggled to keep the tireless Rebić in check. The Eintracht Frankfurt wide man often tucked inside and made clever runs in between Jørgensen and Denmark’s left-back, Jonas Knudsen.

Indeed, it was Rebić’s ingenuity from wide that allowed Croatia to hit back immediately having fallen behind. The 24-year-old raced onto Knudsen’s sliced clearance from and spun clear of left-back before poking a clever through ball into Rakitić.

The Barcelona midfielder’s cross blasted into two Denmark bodies before falling to an obliging Mandžukić.

Pace from wide areas has been a feature of Croatia’s play throughout this tournament, with one-time Manchester United transfer target Perišić and Rebić offering a potent mix of industry and craft.

With Denmark dropping relatively deep, the Croatian full-backs, Šime Vrsaljko and Ivan Strinić, were allowed to advance and support the two wingers, adding up to a deeply uncomfortable night for the Danish full-backs, Knudsen and Dalsgaard.

Sadly, they were unable to keep up the blistering pace as Perišić and Rebić’s influence faded following the half-time interval.

Mandžukić and Cornelius like night and day

Mandžukić is an excellent striker and perhaps somewhat unappreciated. At Juventus, Gonzalo Higuaín is looked upon as the goalscorer-in-chief but the Argentine cannot play the lone frontman role with quite as much physicality and grit as Mandžukić.

The 32-year-old once again poured everything he had into the Croatian cause. It wasn’t always pretty but it was effective, with Mandžukić giving Jørgensen and Simon Kjær plenty of headaches throughout the evening.

Of course, Mandžukić is more than just a bit of muscle up front. His experience informs his decision-making and it was no coincidence that he popped up in the right place at the right time to stab home the equaliser.

At the other end, Andreas Cornelius was anonymous, doing little to justify his inclusion from the start. The one-time Cardiff City striker struggled to impose himself on proceedings in the same manner as Mandžukić, chasing shadows and failing to sufficiently unnerve Dejan Lovren and Domagoj Vida.

Cornelius was replaced by Nicolai Jørgensen., subject of Newcastle United transfer rumours after 66 minutes.

Eriksen goes missing

Denmark are a chore to watch. The only time that changes is when Christian Eriksen springs into life. The Republic of Ireland found out how devastating the Tottenham Hotspur playmaker can be in the play-offs but, against Croatia, he went missing – and Denmark suffered as a result.

This game was billed as the ‘Battle of the Midfield Maestros,’ pitting Modrić against Eriksen. In truth, neither of them featured. However, whereas Perišic and Rebić can make up for Modrić having a quiet night, Denmark rely heavily on Eriksen’s creativity in midfield.

When Eriksen did get a glimpse of goal, he was strangely indecisive. In the 74th minute, he picked up a lay-off from Jørgensen and dropped the right shoulder. So often in the past, we have seen a missile launched from his right boot but the resultant stabbed effort portrayed a man with dented confidence.

Of course, Eriksen is just one of many stars at Spurs but the spotlight is much more intense when he is playing for his country. His goalscoring record through the qualifiers was excellent and he made light work of Ireland but he has struggled to deliver for the large part in Russia, with his goal against Australia being the obvious exception.