This video can not be played Head coach Steve Clarke is leading Scotland into their first men's World Cup since 1998.

"This time, it's a different Steve Clarke." The Scotland boss feels like a new man - and he is sensing a fresh wave of optimism as he leads his team into a third major tournament.

The 62-year-old ended a finals absence of more than two decades when he guided the men's national side to the Covid-impacted Euro 2020. Play-off heartache in their quest to qualify for the 2022 World Cup was followed by the Scots roaring their way to Euro 2024.

"I've not really enjoyed the previous two tournaments if I'm being honest," Clarke tells BBC Scotland in a candid interview.

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So why? Reduced crowds, two group games at Hampden and another at Wembley "didn't give the feel of a tournament" at Euro 2020, he says.

On their showing in Germany two years ago, he adds: "We let ourselves down. We didn't play as well as we should have done and I probably didn't make the decisions that I should have."

Clarke is convinced he and his players have learned from those experiences and are now in a position to "break that glass ceiling" by progressing to a historic knockout tie.

"What we've achieved up to now is great," he says. "Let's see if we can achieve a little bit more."

From risk of death to the oldest man at World Cup Scotland's fateful 1978 World Cup campaign still resonates.

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Clarke points out that a high number of his squad have tournament experience. A chunk of them have two tournaments' worth.

"Now we have to show that tournament experience in a tournament," he says. That starts on Sunday (02:00 BST) when a World Cup group opener against Haiti officially ends Scotland's 28-year absence from football's grandest stage.

Even after the astonishing qualification-clinching victory against Denmark in November, there was a shift in mood following underwhelming displays in back-to-back friendly defeats against Japan and Ivory Coast.

That intensified somewhat when news broke that Clarke had penned a new four-year deal at the end of last month. But the vibe around the national team has changed, with Clarke notably positive after warming up for the tournament with a 4-1 win over 10-man Curacao before smashing Bolivia 4-0.

That positivity will still amount to cautious optimism for most of the Tartan Army. Clarke acknowledges these positive vibes are yet to be transferred to competitive football. There is no denying confidence is quietly bubbling away, though.

The Scotland boss referenced it himself but stressed his players are not "over-confident". "They understand the challenges ahead and when they come, we'll be ready for them," he adds.

"I'm trying to soak it up. I wanted to go to a World Cup as a player. I didn't manage to do that. It's taken me 62 years to achieve what I wanted to achieve, so I'm going to try to enjoy it."

Two summers ago, Scotland's Euros opener proved to be one of their biggest letdowns under Clarke - a 5-1 loss to hosts Germany. "We have to remember how bad that felt," the head coach says.

Clarke believes that crushing defeat put Scotland "on the back foot" for the remainder of their tournament, which again ended at the group stage. "This time, we have to make sure we start on the front foot," he insists.

On the evidence of the Scots' warm-up displays, there are signs they can achieve that against a similarly-ranked nation this weekend.

The recent adoption of an aggressive 4-4-2 shape with two strikers playing centrally and direct winger Ben Doak operating off the right feeds into the idea of a "different Steve Clarke", although he suggested he has been unfairly "tagged with a label".

"I think I've shown consistently throughout my time that I'm prepared to try something different," says Clarke, who feels he has his best depth across a Scotland squad.

"Going into this tournament, the something different was to think about maybe playing 4-4-2 to see how it worked. What people don't understand is when you're at a club you can work on a system for a long period of time and have a lot of training sessions on it. When you're in an international camp you don't have that."

Away from the relentless preparation in the Charlotte sun, the Scotland boss "can't wait to see" his grandkids when the Clarke clan arrive in the US.

The squad will be granted extended family time over the weekend in Boston, something that was not such a luxury in Germany two years ago.

"I phoned back home a couple of days ago and [the family] are all absolutely buzzing, especially the little ones," Clarke says.

"It's probably something we've learned from the last tournament. We played the game, you saw your family for 15-20 minutes, then we were away to the base and they were back to their hotel. So, we decided this time we would try to incorporate a lot more family time so people can be around their loved ones, whether it's a good result or a bad result."

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