By
BBC Scotland's chief sports writer in Charlotte
Scott McTominay is talking about mentality, about dig and dog and how some players have it and how some players just don't.
That refusal to stop and give up? He says he's had it since he was a kid and knows that every last man in the Scotland changing room has it, too.
"Not willing to stop when it gets tough, it's one of the most important things in football," he tells BBC Sport, before talking about a guy who, to him, embodied that uncompromising nature every day - Michael Jordan, the NBA colossus of yesteryear.
"He once said that whenever somebody arrives to the stadium they could be watching for the first time," McTominay explained. "So if you're not giving your absolute best a young fan could be walking away going 'he wasn't that great'."
The Scotland midfielder says he's been doing a bit of that in training, a mentor but also a taskmaster for the youngsters in the squad, such as teenagers Tyler Fletcher and Findlay Curtis.
"I'm demanding and quite hard on some of them," he says. "The right way to live your life off the pitch is probably more important than what you do on the pitch because you can kill your whole career by things that you do off the pitch.
"They need a little bit of tough love sometimes, young players. I had that. There was a lot of senior pros saying, 'Listen, you've got to up your game or you've got no chance'. I don't want to name names. It was a lot. Behind closed doors.
"And the things that get said are ruthless - sink or swim."
McTominay on winning mentality
'Jose dressed me down... I thought it was over'
McTominay grew up in a tough school, entering the Manchester United development set-up aged five.
He left home in Lancaster at an early age to become part of a residency programme at the club, an emotional upheaval that presented challenges to a boy who spent much of his early years flying well under the radar.
He was no childhood prodigy, no sure thing.
In his first season of under-18 football he barely saw two hours of competitive action. He was only 5ft 6in at 16 - a "silky number 10" as he put it. In his debut season with the under-21s he started two of 22 matches.
His growth spurt was something to see, from a diminutive attacker to a beast at 6ft 4in. His bolshiness seemed to grow in proportion with his height.
That tough love he talks about now began around then. He tells a story of a day spent training with the senior team and how he vented when all the tight decisions in a bounce game were given in favour of the "old lads" and against the "young lads".
Did McTominay find his mum in the crowd?
Jose Mourinho was his manager who later became his champion.
"Jose phoned me because I was arguing with Michael Carrick and Ashley Young," McTominay recalled. "There were a couple of swear words in there. He dressed me down. It was like 'who do you think you are, you've done nothing'. I thought it was over [at United] before it started, how forceful he was."
It wasn't over, it was just beginning. McTominay made his senior debut in May, 2017. "This kid has everything I want," said the manager.
The following season, Mourinho invented a new award at the end of campaign ceremony, making McTominay the manager's player of the season. "He started the season in the academy and ended it playing big games in the Premier League," said the Portuguese. "I thought this kid cannot go home without an award."
McTominay was a Scotland player by then, capped in March 2018 against Costa Rica.
There was a brief crossover between Steven Naismith exiting the international stage and McTominay bursting on to it, but Steve Clarke's now assistant, remembers how the young man was back then.
"He kept himself to himself," he said. "At the start I thought, is that because he was born in England and it's his (father and his) grandparents who are Scottish? He's maybe just a wee bit unsure of the Scottishness, the bluntness of Scottish people? But over the years, he just matured."
'One of the best midfielders in Europe'
McTominay was born into a difficult era at United. Ole Gunnar Solskjaer succeeded Mourinho and loved the youngster. He gave him 22 games, then 37, then 49. He called him a "physical monster". His engine was unreal even when the team was not.
Ralf Rangnick succeeded Solskjaer and talked of McTominay as a future captain.
The problem was that Old Trafford was in turmoil. When the United fans rounded on players then their local boy, the lifelong fan, was one of the first to get it.
Playing in a deeper role instead of the box crasher he has become, he came in for special treatment. Tough love? At times, it was savage.
Rangnick made way for Erik ten Hag, who simultaneously praised McTominay's fighting qualities while at the same signing a battery of players in his position.
He could have left for West Ham for £30m but stayed. Newcastle, Fulham and Bayern Munich were said to be interested. Nothing happened.
McTominay, Tierney or McLean?
In October 2023, United were trailing 1-0 at home to Brentford when McTominay came off the bench with 10 minutes to go. He scored twice in added time to win the game.
He gave one of his most famous quotes in the aftermath, words that reflected his frustration but also his fierce determination. "Never give up, man," he said. "You never give up. No matter the situation you never give up, never throw the towel in."
It's said that McTominay did not give up on United but that United gave up on McTominay. Things were stressed. Money had been wasted. The club needed to sell in order to buy.
He left for Napoli. A succession of his former United managers rounded on the club for letting him go. "I'm almost shocked," said Solskjaer. "This decision is beyond me."
It wasn't long before Mourinho was calling his former wunderkind "one of the best midfielders in Europe".
"When I think of Scotland, I think of my boy Scott McTominay," he said. "I got him when he was 18, when nobody at Man Utd believed he could be the player he is."
'It's like in Super Mario when you get a mushroom...'
Return to Napoli
His Napoli years - the Serie A title in 2024-25 and the adoration that came with it - have turned him into a player who is worshipped in Naples and identified throughout the world.
McTominay is the superstar of this Scotland team, the guy with a giant mural on the side of a house near Hampden and whose frame - mid-bicycle kick against Denmark on the night of all nights last November - is on a bank note.
For club and country he has scored 13, 16 and 17 goals in the last three seasons, some of them to win a title in Italy, others helping Scotland to the World Cup.
McTominay has 70 caps and has played multiple positions - right-sided centre-back, defensive midfielder, attacking midfielder. He is now exactly where he wants to be, in every sense.
Naismith has watched him grow into a player of huge substance, on and off the field. "He can glide across the pitch with elegance. He's such an athlete," he said.
"And see his passing - it's as if you're in a computer game. It's like in Super Mario where you get a mushroom and you're bigger, if that makes sense. He's just more powerful than everybody else.
"The last part is you just hope he's not an arsehole - and he's not. He'll hang about with the youngest players in the squad at dinner and he'll chat away to them.
"And then the next day he could be sitting with [John] McGinn and Robbo [Andy Robertson] and Kenny McLean and Grant [Hanley] and be part of that.
"And then he might just be by himself for a bit. He's a social butterfly and it's all pure happiness for him."
It's taken a lot of hard work to get McTominay happy. A nation will be hoping he's still smiling in the wake of their opener against Haiti, Scotland's first World Cup game since the great thoroughbred in their midfield was barely out of nappies.