Hydration breaks, ice jackets, cooling towels and isotonic drinks have been a feature of the World Cup so far as hot weather impacts matches.

Some games may have been played in air-conditioned stadiums and at more modest temperatures across North America, but for Scotland it is about to heat up.

The opening win over Haiti in Boston was played at around 25C and, although Steve Clarke's side return to the same venue to face Morocco, the kick-off being three hours earlier means warmer conditions are likely.

It is forecast to be around 27C come kick-off on Friday (23:00 BST), and Scotland's final group game in Miami against Brazil next Wednesday is predicted to be even hotter.

Temperatures could be over 30C for that one, and with nearly 80% humidity expected it will feel much more than that.

Scotland have prepared for this, but it could still have an impact. Even if Steve Clarke is comfortable with joggies on at training.

Scotland flew out early to Fort Lauderdaule at the start of June so they could get used to the hot weather as soon as possible.

There was sun cream, tan-lines and ice buckets as the players were put through their paces before their final warm-up win over Bolivia in New York.

Their training base is in Charlotte, North Carolina – which is roughly between Boston and Miami – and temperatures there have hit 30C.

Before they had even set foot in the US, some of the squad went to the University of the West of Scotland to use their extreme environments chamber, which was able to mimic the Florida conditions.

"It's 10 or 12 days that Scotland have been there so the acclimation and adaptation to the conditions has probably taken place quite nicely," Vish Unnithan, a professor of sports science and exercise physiology at the university, told BBC Scotland.

"Maintaining hydration and fluid levels, but also nutritional recovery is going to be key. We know when you're exercising at the intensity these guys are exercising in the heat, the rate at which you use stored carbohydrates is much faster.

"So the nuitritionists with the Scotland team will be key to making sure the carbohydrate intake is where it should be."

Unnithan also says because players sweat at different rates, there will be individualised programmes to allow them to stay hydrated and recover properly. Different gels and drinks will be offered to different players.

Morocco and Brazil have players who are far more used to living and playing in the heat, which gives them an edge.

However, after a long club season residual fatigue is a factor at any tournament, but particularly one played in roasting temperatures.

That is where Scotland might have an advantage. Looking at the starting XIs from the opening games in Group C shows the Scottish team have fewer miles on the clock in the last year.

Only Scott McTominay, John McGinn and Lewis Ferguson had hit 50 games before the World Cup started (all 53), while Morocco had six different players in their team against Brazil who did so.

Brazil also had three players on at least 50 games, but their starting side had played a total of 475 games last term, compared to Scotland's 410.

There is a fine line between being fresh and being undercooked, though.

Ben Gannon-Doak shone for Scotland in their win against Haiti, but had to be replaced on 75 minutes because of his "calves leaving the stadium" before he did.

That might be a result of the winger's limited game time this season, having missed most of Bournemouth's campaign through injury.

As Clarke said before the tournament kicked off, this will be a World Cup where most of the 26-player squad is utilised.

How Scotland approach the match in the conditions will also be a factor.

The game against Haiti was a nervy affair, with both sides regularly giving up possession in a fairly fenetic encounter.

Scotland only had 46% of the ball against the weakest side in the group, and though they may come out with a similar number against Morocco and Brazil, taking care of the ball is a priority in the heat and humidity.

Graeme Souness captained Scotland against Brazil in the heat of Seville at the 1982 World Cup.

"The problem when you play in heat is if you keep giving the ball away, sooner or later someone's going to punish you," he told the BBC.

"And I just felt, in the second half [against Haiti], when we were holding on to that lead, we should have been better at that. Don't give the ball away. Good players don't."

Former Scotland striker Stuart McCall believes Clarke may sacrifice one of his strikers to bolster the midfield to add more mobility and try to add control.

"I would imagine they'll take Lawrence Shankland out and add another midfielder," he told BBC Scotland.

"Whether that's Ryan Christie or Kenny McLean, who could sit in with Lewis Ferguson and let Scott McTominay play as a number 10 a bit further forward."

The hydration breaks 22 minutes into each half have also been a signifcant talking point at the World Cup so far, which Scotland will aim to use to rest and rest.

At last summer's Club World Cup in the United States some teams like Bayern Munich even left their substitutes in the air-conditioned dressing room during the first half, rather than have them getting too hot on the bench.

One way or another, the conditions will have to be factored in to the game itself as well as the preparation.