Three years ago, when Sheffield United convened their first pre-season training camp under his tutelage, Chris Wilder noticed one member of the squad which would go on to win League One at a canter struggling in the heat.
It is a story he likes to tell now because, as he prepares to win a second senior international cap, it reveals the progress John Fleck has made. Both in terms of his fitness and his profile which, after making a strong start to the new top-flight campaign, has placed him at the heart of Steve Clarke's plans to transform Scotland's fortunes.
"We were out in Spain when we were first here," Wilder remembered. "John's condition now isn't what it was then and that's not being critical. I can just picture this kid in Marbella, when we were doing a session on a Tuesday afternoon, gasping for breath. Now he just goes and goes and goes."
United always knew Fleck had potential. That is why they signed him. But not even the midfielder's biggest cheerleader could have suspected, after he swapped Coventry City for Bramall Lane, quite how rapidly his career would blossom. A graduate of Rangers' youth system - he made his professional debut for the club aged 16 - Fleck moved to the Ricoh Arena in 2012 following the Glaswegian giant's financial implosion. Despite impressing in the Midlands, he spent long periods of his time there simply treading water as City were also engulfed by off-the-pitch problems.
Having made his 150th appearance for United at Tottenham Hotspur last weekend, Fleck has been a driving force behind their climb out of the third tier to fifth in the Premier League. Although his predecessors' failure to recognise the 28-year-old's talents has been the subject of much debate, Clarke has made him a regular pick. Together with Oli McBurnie, who United's record transfer signing, Fleck is expected to feature when Scotland face Cyprus tomorrow before Tuesday's meeting with Kazakhstan. Unable to qualify for Euro 2020 via the group stages, Clarke's men are guaranteed a place in the play-offs by virtue of their recent National League results.
Like his United team mate John Lundstram, who failed to make the grade at Everton before moving to South Yorkshire via Oxford, Wilder believes the challenges Fleck faced as a youngster have made him a better player now.
"Technically, John and John are very good," Wilder said. "They've also had disappointments when they were younger and they've also got the character to bounce back. That goes an awful long way in terms of the makeup of a player."
"It isn't always over when someone gives you a bit of bad news early in your career," Wilder added. "It's about how you handle the disappointments as much as the good times. And that's what they've done, which tells you a lot about them. They've had the character to come back."