Scotland assistant coach James McFadden wants to help create a belief among the squad that will help drive them back to a major tournament.
The former international, 34, is part of Alex McLeish's management team, who were given their first opportunity to work with the current squad on Monday.
Scotland face Costa Rica and Hungary in friendly matches over the next eight days and several players could debut.
"We need to see if they're good enough," said McFadden.
"It's a chance for them to force their way into the team or the Nations League coming up [in the autumn].
"We've seen them do well for their clubs but it's a step up, international level, and it's a chance for them to be part of something we believe is going to be really special.
"We have to use the friendlies for what they are - to see other players and what they can do. We know what the guys who played the last campaign can do and we're not saying they're not good enough."
'We'd win awards for talking our game down'
Nine uncapped players were called up when McLeish, who has taken on the national job for a second time, named his squad last week and another, Jack Hendry, was added to the group following injuries to established international defenders Kieran Tierney and Russell Martin.
Goalkeepers Jordan Archer and Jon McLaughlin, defenders Barry Douglas and Scott McKenna, midfielders Kevin McDonald, Dylan McGeouch and Scott McTominay, and forwards Oli McBurnie and Jamie Murphy are all in contention for a first senior cap.
And Tom Cairney, Callum McGregor, Ryan Christie and Jason Cummings have one cap each, with only seven players in the squad with more than five caps.
"The younger ones have got to come with a belief and a freedom to go and express themselves," added McFadden.
"For so long we've talked our game down. We'd win awards for that. But we need to start talking it up and bringing that belief that young players can come in and impress.
"I didn't listen when people said you couldn't do stuff and I want them to come in with that attitude of, 'I want to be the man, I want to achieve something for Scotland'."
One player left out of the squad was Hearts captain Christophe Berra, who had been a regular in the side under McLeish's predecessor Gordon Strachan.
"We've got quite a lot of left-footed defenders," explained McFadden. "It's really unusual.
"We need to find a balance in the side, we can't keep going with left-footer, left-footer, left-footer.
"We know what Christophe can do, he's experienced. To bring him when you're trying to see other players, is it fair? It's one where the manager knows what he can do and we have to look at other players."