Fear the Jags, says Jonny Glen.

No, not Partick Thistle, redoubtable though they might be. Scotland's eager young pup of the cross-country circuit was enthusiasm personified in the week leading up to his departure for China ahead of tomorrow's world championship, except when it came to the mandatory inoculations required. "I was a bit of a woose," he confirms. "I just wasn't looking forward to it."

With his needle nightmares behind him, it has left the unfamiliar cuisine as the 18-year-old's chief trauma. A small sacrifice, Glen will attest, among the many hardships endured and treats deferred during what has been a rapid ascent into the leading pack of British endurance hopefuls over the past 12 months.

Recently crowned as UK series champion for his winter's work, it was not so long ago that he was pledging to hang up his spikes, dispirited by trailing his peers home in a manner that shrunk his natural exuberance for ploughing through even the muddiest terrain.

"My Dad," he recounts, "always kept telling me it's not a level playing field. 'There are big boys who have developed at a younger age and they do well and stand out at that age'. I took a while to come on but my coach played things really smart, building up my mileage very steadily.

"Maybe those other guys who have been running long from a young age have nowhere to go now whereas I've developed and kept it sensible and it feels like I'm starting to come into my own now."

An apprentice electrician in Greenock, he always aspired to be a bright spark. Football, as for so many, looked at his physique and stereotypically stuck him out on the right wing, confident he could run up and down the flank without complaint. It became, while it lasted, simply a surreptitious means to practice his favoured trade.

"I didn't think I'd ever make it as a footballer but I had to make the choice between that and running. Athletics was the clear-cut winner. I played with Port Juniors boys club. We won the league a couple of times but after that, the team wasn't up to much and I much preferred running."

As he enlarged in size, he also grew in stature. Scotland has punched above its weight in recent years in nurturing exponents of cross-country, over-achievers like the Hawkins brothers, Derek and Callum, as well as his colleagues in the Great Britain & Northern Ireland team in Guiyang, Andy Butchart and Rhona Auckland.

It makes for healthy domestic competition before the border south is even crossed. Glen, through his endeavours, has had his horizons exponentially widened during a cross season he describes as "surreal". Opportunities knock with a string of American collegiate suitors keen to procure his talents.

"There's been quite a few," he confirms, "but I don't know how seriously to treat them. A bunch of them have just come through Facebook, nothing very formal, saying: 'look, we'd be interested so drop us an email if you'd like to chat.' Even Harvard sent me a message, saying they'd offer me a place. That just wasn't happening. I didn't even bother replying."

Their loss, Inverclyde's gain. Yet his Chinese trip is both an end and a beginning, the winter season's close and the start of a track campaign where Glen hopes to transfer terrains and make a similar impact. He was one of those who savoured the chance of circling Hampden last summer. Rather than the Commonwealth Games, it was to claim victory in the Scottish Schools Championships over 5000m. Time remains on his side.

His goals this weekend will be measured in placings, not the clock. "I've looked at previous results and I saw Jonny Davies finished 35th a couple of years ago," Glen states. "I'm not sure if that's a good target. But the top half would be good."