The midfield head-to-head between Scott McTominay and Ayyoub Bouaddi could be vital.

Last weekend in Boston, Scotland played their most important game of international football in 28 years, a walk on the wildside against Haiti, a game that put the heart sideways in every Scot but, ultimately, sparked the party to end all parties in the city they called Beantown. More like Beanotown, more like Scotland, Massachusetts.

For almost four decades there was a character in the DC Thomson comic called Ball Boy, a wee football-obsessed lad who couldn't kick a can down a street without thinking he'd scored the winner in a World Cup final. Boston has been overtaken by Ball Boys, full-time dreamers and relentless ambassadors for their country. There isn't a cop in the city who hasn't been charmed by them, nor a local business that hasn't benefited hugely from the Tartan Army dollar. They've been a happy whirlwind, a force of nature that will be missed when it blows out of town in the coming days.

Before the exodus, though, there's a job to be done. Such is the rarefied air they're breathing at this World Cup, what we said in previewing Haiti can be said again in looking forward to Morocco.

Scotland's Boston love affair one for the ages. What are Clarke's big calls for Morocco? And who would you pick? Why does Scotland's McGinn do goggles celebration?

World Cup: Scotland's Biggest Test Yet. After the big one comes the ever bigger one. Bigly, as somebody once said. This one, if it goes well, could be the greatest of them all, not just in 28 years but, arguably, in the 154 years since Scotland played England at the West of Scotland Cricket Club in the first international match ever. Then, as now, Scotland were captained by a man with firm roots at Queen's Park.

A 0-0 draw then would go down a storm now. Stalemate against Morocco would almost certainly send Steve Clarke's boys into the promised land of knockout football for the first time in the nation's history. Even a narrow defeat would be good news given the way the permutations are shaking up for the best third-placed qualifiers.

Robert Gardner was the man who led Scotland in that pioneering contest of 1872. A full Victorian moustache and well-groomed beard, it's nice to imagine him up there in football heaven, his whiskers twitching as he watches the action from the Boston Stadium, a little bit of a step-up from the arenas he'd have been used to.

Summoning up history is appropriate because even before Scotland set foot in the USA they were doing it themselves, manager and players laying it on the line about what their target was - becoming the first of their kind to make it out of a group in a major championship. It was hairy against Haiti; a deflected winner, a Grant Hanley handball in the box not deemed a penalty, a magnificent Hanley block denying a near-certain goal, a late Frantzdy Pierrot header that went just wide instead of going where many thought it was going - into the back of Angus Gunn's goal.

Scotland had their moments, too, of course, but it was a sticky effort and none of the players are arguing otherwise. A brilliant victory in a pressure-filled, must-win game, but a performance that was beneath them. These players are capable of more than they delivered against Haiti. And now is the time to prove it.

At various points in qualification, good fortune shone brightly on Scotland, but luck always runs out in the end. The likelihood of Morocco, ranked the sixth-best international side in the world, being held or beaten on the back of big breaks going the way of the underdogs is a dream too far.

Scotland are going to have to be resilient, organised and inspired to get a draw or even a one-goal loss. To win, they need to put in the best display we've seen from them since Clarke took over. This video cannot be played 'I was only four' - Andy Robertson on last Morocco meeting.

Anything below par and Morocco, with their speed and creativity, will give them a rough night. The jeopardy is intoxicating. In their 1-1 draw with Brazil on Saturday, Morocco bossed the show early on. They ran rings round the South Americans for a spell. In the first 30 minutes, they had 12 shots on goal. When they scored, it was a microcosm of their class, a lethal moment of accuracy and brilliance.

Brahim Diaz's pass was threaded between Gabriel, Premier League winner with Arsenal, and Marquinhos, double Champions League winner with Paris St-Germain. Ismael Saibari's lobbed finish was gorgeous and too much for Liverpool's Alisson. That's a slight lack of concentration from two world-class defenders and one of the finest goalkeepers on the planet undone by two touches.

Brazil head coach Carlo Ancelotti made two substitutions at half-time. Casemiro was hooked because a teenager was making him look like an old man. Ayyoub Bouaddi is 18 and is the breakout star of the tournament so far. He plays for Lille, but soon he's going to be playing for one of Europe's elite clubs and they'll be paying plenty for him. Current price tag: £61m. Bouaddi has technique and vision. He made his Conference League debut at 16 - the youngest player to have featured in a Uefa club competition. He's also the youngest to have played a top-flight game in France in the 21st Century.

Morocco haven't lost a game in two and a half years. There's an asterisk beside that stat, of course. They were defeated by Senegal in the final of the Africa Cup of Nations in January only to be awarded a 3-0 victory later on by the Confederation of African Football. Senegal were sanctioned for walking off in protest for 15 minutes after a penalty decision went against them. Chaotic doesn't begin to cover it.

This video cannot be played 'I'm not going to eat much' - Steve Clarke on change of shape. Despite winning all of these games, Scotland's opponents don't tend to score many goals, which is a surprise. In Diaz and Saibari and the left-sided midfielder, Bilal El Khannouss, they have hugely dynamic attackers. And, in Achraf Hakimi, they have one of the best right-backs in the world, if not the absolute best.

Hakimi is the heart of it. Born in Spain to a street vendor father and a mother who was a cleaner, he has spoken often about how his upbringing shaped him. The Paris St-Germain defender will stand trial for rape, French prosecutors have confirmed. Hakimi denies the accusations. Hakimi is a magnificent footballer, at his best when going forward, an explosive force down the right for Morocco, a Serie A winner with Inter, twice a Champions League winner with PSG, a World Cup semi-finalist with his country four years ago.

Morocco are a team drawn from the diaspora. Of the starting line-up that drew with Brazil, their goalkeeper was born in Canada, two of their defenders hail from Spain, another from France and another from the Netherlands. Neil El Aynaoui, the midfielder, was born in France, Bouaddi and Saibari in Spain, El Khannouss in Belgium. In the rest of the squad there are another nine players who originated in Spain, Belgium, France and the Netherlands. Clearly, though, they are Moroccan to the core of their beings.

They represent a ferocious test for Scotland - and also an opportunity. Only a handful of Clarke's team produced their best stuff against Haiti and none of them are hiding from that. Scott McTominay was one of them. Maybe still feeling the impact of a tummy bug or, perhaps, weighed down a touch by the burden on his shoulders, the talisman was not all that talismanic. He ran his heart out - with all nations having played one game, he ranked sixth overall in terms of kilometres covered - but he wasn't the influence he can be. Nor was John McGinn, despite his goal. It didn't matter on the day, but it will matter against Morocco.

Scotland's totems need to turn up. Clarke is likely to drop a striker and bring in an extra midfielder to cope with Morocco's energy and class, to stifle while also retaining the capacity to strike out on their own. This can't be backs-to-the-wall for 90 minutes. Everything screams 'the biggest test of their international lives', but, also, everything we know about this Scotland team tells us that they are up for a fight.

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