Josh Griffiths' selection for the World Championships has been confirmed after the club runner beat the country's elite men at the London Marathon.
Racing his first marathon, Griffiths was the first Briton across the line to qualify for the World Championships.
The 23-year-old is one of six marathon runners selected by Great Britain for August's competition in London.
The others are Callum Hawkins, Robbie Simpson, Alyson Dixon, Charlotte Purdue and Tracy Barlow.
It is only the third time that British Athletics has selected six marathon runners to compete at a World Championships.
Dominic King will be the first 50km race walker to represent Great Britain at a World Championships in 22 years.
Griffiths' 'crazy' qualification
Griffiths had entered the London Marathon hoping to qualify for the Wales team for next year's Commonwealth Games in Australia's Gold Coast.
Not only did the Swansea Harrier manage that feat, his time time of two hours 14 minutes 49 seconds saw him secure an unexpected place at the World Championships.
"It's crazy. You almost don't believe it's going to happen," he told BBC Wales Sport.
"It's such a jump from where you're at, so to make that jump is just surreal.
"To be back in London in the summer, competing in front of those crowds, it's going to be great."
Griffiths will graduate with a masters degree in sports coaching from Cardiff Metropolitan University in July.
But he says the rest of his summer plans are now going to have to change.
"I thought I'd maybe have a week away somewhere nice and relax a little bit," he said.
"But now it's full steam ahead towards the World Championships."