Grant Hanley and Jack Hendry showed up well in Scotland's opening game, both making vital interventions as Haiti came on strong in search of an equaliser after John McGinn's strike.

Whether head coach Steve Clarke retains that centre-back pairing or reintroduces the fit again Scott McKenna – he could switch to a back five and play them all – the entire Scottish defensive unit will need to show the ferocious desire to protect their goal that Cape Verde did so impressively against the Spanish.

"One of the big things Cape Verde work at, and the manager has talked about it, is the culture of the country itself and making sure that everybody buys into that. If you do that, everyone will work for each other," said former Scotland winger Pat Nevin after covering the match at Atlanta Stadium for BBC Radio 5 Live.

"Boy, what a sight of players working for each other we saw. They spent the vast majority of the game on their own 18-yard line, not all of it, and when they broke, they were brave and they broke in numbers.

"To do that and keep that level of concentration, you don't do that if you're a bunch of individuals, you only do that if you're a group, if you're a team, if you believe in each other. And it shone through.

"I watched Sidny Cabral start the game and thought, 'oh, my goodness, there's a disaster waiting to happen' because of the way he was tackling - but he got every one of them right.

"You look at Diney Borges, again, he looked like he was a kitten at the start of the game. By the end of the game, he was a lion."

While defensive organisation and resilience was the foundation of Cape Verde's performance, they still managed to retain some semblance of attacking threat on the counter-attack, especially late in the game, to relieve some of the pressure at the back.

They might even have snatched a famous victory, with defender Borges going close with a late header and a couple of late counters threatening to catch Spain out as they poured forward looking for a winner.

Scotland will need to give the Moroccan back-line something to think about if they are to avoid a dangerous pattern of being pinned in on the edge of their own box.

Former Scotland winger Neil McCann believes the presence of Ben Gannon-Doak, a standout performer against Haiti, will be crucial in getting the Scots up the pitch.

"Ben Gannon-Doak is obviously a very big weapon for Scotland in terms of how he eliminates people in the wide area," McCann said.

"He's shown in his Scotland career already that he can play off the left, off the right, and standing people up and just going past them like they're not there.

"The one thing I want to see him work on is his final ball. Getting past people generally isn't a problem. It's what you do once you're in that position.

"It doesn't matter who he's playing against, whether it's [Denmark's Patrick] Dorgu, whether it's Achraf Hakimi against Morocco, I still think he'll create chances."