While in Canada for a fishing trip, Josh Herzog drove past the Winnipeg Blue Bombers' stadium. He pulled out his flip phone, snapped a picture and started pecking a text message to his best friend from high school, from back in Detroit Lakes, Minn.

Herzog had played sports with Adam Thielen since they were little kids; he would one day be the best man in Thielen's wedding. Herzog had watched how Thielen had sprouted a couple of inches since high school, how he'd gotten faster, how he'd started to pile up gaudy receiving stats at Division II Minnesota State. Thielen's dreams had expanded, and now Herzog wanted to send him a slice of encouragement.

"You could be playing here someday," Herzog wrote, with the picture of the Canadian Football League stadium attached.

"Bro, that would be awesome," Thielen replied.

In the years since playing in the CFL seemed audacious, Thielen has advanced further than anyone imagined. After high school, he received his only scholarship - for $500 and books from a Division II school - at the 11th hour. After college, he gained notice at a regional combine he paid $250 to get into. After his first NFL training camp, Thielen passed through waivers and joined the Minnesota Vikings' practice squad. And after five years in the NFL, the lanky kid from Detroit Lakes has morphed into one of the best football players in the world.

Once unknown and undrafted, Thielen, 28, is a reigning Pro Bowler still on the ascent. The $27 million contract he signed last year now counts as a remarkable bargain for the Vikings. Thielen leads the NFL with 58 catches, which puts him on pace to break Marvin Harrison's single-season record of 143. He also leads with 712 yards, five more than Julio Jones and 55 clear of third-place DeAndre Hopkins. Thielen has recorded at least 100 yards in all six Vikings games, the longest streak to begin a season since 1961.

"It's exciting and emotional at the same time," Peter Thielen, Adam's father, said. "Sometimes, you get emotional, you're just excited and happy for him and everything else."

As evaluators missed him for a decade, Thielen forged ahead with daily improvement and quiet, unwavering belief. Back home during college, Thielen was out with friends in Detroit Lakes when he ran into a linebacker from North Dakota who was bragging about an upcoming pro day, how he was headed to the NFL. When Thielen replied he'd play in the NFL someday, too, "the guy literally laughed at him," Herzog said. Nobody is laughing anymore.

"The seriousness of how Adam has been taken through a lot of his career, the credibility, I think it's been a big motivator for him," said Todd Hoffner, Thielen's first coach at Minnesota State. "I think a driving force has just been his providing proof that he belongs, and he can be one of the best players in the NFL."

Now that Thielen stands at the highest echelon of his sport, there are two obvious questions. How could one of the most talented players in the NFL have been so overlooked? And what convinced Thielen he could make it? The answers to both threaded through his path.

Thielen was young for his grade in high school, just 16 years old at the start of his senior season two-a-days. Thielen stood 6 feet and weighed 160 pounds and, coaches estimate, ran the 40-yard dash in 4.9 seconds on a good day.

"I don't really blame any of the [college] coaches for not really looking at him," Herzog said. "He had the skills it took, but he just physically didn't have it. You couldn't predict he was going to get to 6-3, 200 pounds. At the college level, he wasn't going to cut it. He hadn't developed physically."

Thielen, though, possessed natural athletic gifts. As a sharpshooting guard, he set Detroit Lakes High's all-time scoring record. He played summer league baseball, just because. He played to about a 5 handicap on the Detroit Lakes state championship golf team, "and he didn't play a lot of golf," Detroit Lakes athletic director Rob Nielsen said. Thielen jokes these days about joining the tour after his football career.

Detroit Lakes used a run-heavy, split-back offense. When they passed, they'd play-action and heave it deep to Thielen, knowing he'd somehow come down with the ball. His coaches gaped at one another and ask, after Thielen had pinned a ball to his leg or snared one behind his back, "Did you see that catch?" Thielen worked for Herzog's family's roofing company in the summer, and Herzog would be amazed how every time he tossed something down to him from the roof, Thielen would catch it.

"What we saw every day, it's hard to sell that to people who just see he's not fast," said Nielsen, an assistant coach for Detroit Lakes when Thielen played.

When high school ended, Thielen told Herzog he was 98 percent sure he was going to Concordia, a Division III school in Moorhead, Minnesota, where coaches had assured him he could play basketball and football. Before he made a final choice, Thielen played in a Minnesota high school football all-star game. Minnesota State's coaches attended practice the week leading up to the game. Flint Motschenbacher, Thielen's head coach at Detroit Lakes, knew one of the assistants. "Nobody's on this guy," Motschenbacher told him. "You should take a chance."

Hoffner offered Thielen what he called the "Maverick 500" - a $500 scholarship. Concordia couldn't offer scholarships as a Division III school. Thielen accepted Hoffner's offer.

Aaron Keen, now the offensive coordinator at Eastern Michigan, met Thielen when he arrived at Minnesota State Thielen's junior season. He found a "football junkie" who would sit for hours with quarterbacks, studying until he understood how his routes would look through their eyes, regardless of the defensive coverage.

"He would get banged up and bruised up in practice because he would go so darn hard," Keen said. "He had a phenomenal senior year. He was unstoppable for us."

After his senior season, Thielen contemplated his future. During the season, he would mention to his parents he wanted to pursue football further, perhaps in Canada or Germany. Minnesota State coaches unsuccessfully tried to convince bigger local schools to let Thielen join their pro days. Over lunch one day, Thielen told his parents he planned to go a regional combine.

"I was a little surprised," Peter Thielen said. "I said, 'What is it?' "

The NFL Combine has become a spectacle, broadcast live as the entire industry converges on Indianapolis. It is a big deal. An NFL regional combine is decidedly not. Eight cities host tryouts for anybody who wants to fork over $250 to do drills in front of NFL scouts. Thielen decided he would attend the one in Chicago. His father cut a check to cover the fee.

A former college teammate, Tommy Langford, had worked with professional trainers when he tried out for pro scouts. From experience he knew Thielen would need help, and he also knew Thielen didn't have money for a private trainer. So for six weeks, Langford worked nights at a Freightliner and taught Thielen new techniques during the day.

At Minnesota State, coaches cared more about quickness than top-end speed, so they never timed players in the 40-yard dash. But the currency of NFL scouts is the 40, especially for players who didn't face top competition.

"If you run a slow 40, they don't even look at your film," Langford said. "It really was make or break."

Even breathing mattered. Thielen learned how to breath in deeply before the start, then let it all out at the start and breathe two or three more times during the sprint.

As he trained and finished classes, Thielen kept an eye on career options in case football didn't work out. He interviewed for a job in dental equipment sales, and when the rep asked him his dream job, he replied, "Playing in the NFL." Both laughed.

"If I'm being real honest with you, I was trying to get him to be my graduate assistant receiver coach," Keen said. "I told him, 'I'm going to save this spot for you.' He would have been a hell of a football coach. I kept saving it, kept saving it. It never did get filled."

Thielen, Langford and another friend drove to the combine in Chicago. When they arrived, Langford and their friend learned only players could enter. They sat in the hotel room and refreshed the combine website over and over, waiting for Thielen's 40 time to show up. He had trained six weeks, and a tenth of a second could mean the launching of a career or starting over. They hit refresh again, and finally a time popped up.

It showed 4.45.

"You would have thought we won the Super Bowl when it was a 4.4," Langford said. "The biggest relief for Adam was knowing, no matter what, he did everything he could to make the National Football League."

For months, Thielen had eaten nothing but healthy food. To celebrate, the trio went out in Chicago for deep dish and beers. One sprint had changed his life.

The NFL invited Thielen to a bigger combine in Texas, at AT&T Stadium. Four times a week, Thielen drove 90 minutes each way from Mankato to the Twin Cities to work out at Englebert Training Systems with trainer Ryan Englebert. In Texas, after another fast 40, scouts from the Carolina Panthers and San Francisco 49ers told him, "We're interested."

The Vikings invited him to their rookie minicamp. He played well enough to bump another wideout off the 90-man roster. In summer, the Vikings benched him for the final two preseason games, not wanting to showcase him, so he could pass waivers and end up on their practice squad.

Thielen kept working. In practice, coaches would yell, "That's an NFL route!" after watching him. He played almost exclusively on special teams in 2015, but he told Herzog he would be the best receiver on the team. In 2016, he caught 69 passes. In 2017, he caught 98 for more than 1,200 yards. This fall, he might be the best receiver in football.

"I know he doesn't think there's a ball he can't catch, for sure," Vikings Coach Mike Zimmer told reporters this week. "That's how he is in practice every day. He laid out in practice the other day and goes, 'Why did I do that?' He comes over and talks to me during games about stuff that's going on and it's always about, 'These guys can't guard me.'"

Thielen's skill and work earned him his lofty place in the NFL, but the serendipity required along the way raises a question: How many Adam Thielens are out there selling dental equipment or climbing the small-college coaching ranks?

If Minnesota State coaches hadn't taken a flier at the high school all-star game, Thielen would have spent winters playing hoops at Concordia rather than honing his routes and improving his speed. If the Vikings didn't hold training camp at Minnesota State, they may have taken a chance on a different minicamp long shot.

"If he goes to that combine and runs a 4.5, you never hear about Adam Thielen," Nielsen said. "That's really the only thing that got him his shot."

Maybe, though, there aren't more like him. It took doggedness for Thielen to attend the combine, and if that didn't work out, he would have tried something else. His natural athletic skills, while not obvious, are special. And eventually, his speed and strength caught up.

"There's a ton of guys like that," Langford said. "Adam separates himself from those guys because he finds a way."

Work, luck, resilience, opportunity - it all came together to make Thielen a wide receiver on the team he grew up loving. As a boy, he pretended he was Randy Moss and Cris Carter and Jake Reed. Now, small-town Minnesota kids pretend they're Adam Thielen.

His son is a millionaire now, but Peter Thielen still works in construction. He raises metal buildings - residential, commercial, garages, whatever. It's a busy time of year, trying to finish jobs before the northern Minnesota winter rushes in. As he was driving to a site Wednesday afternoon, he tried to explain what it is like to see everything that has happened.

"It brings tears to your eyes sometimes," he said.

This article was written by Adam Kilgore, a reporter for The Washington Post.