Late Saturday afternoon, just minutes after the 2015 NFL draft concluded, Nate Boyer's cell phone lit up with a number that made no sense … except it fit perfectly into the story of the NFL's most improbable rookie prospect.

Boyer, a former Green Beret who less than a year ago was involved in combat in the mountains of Afghanistan. It was part of his summer job, if you will, in the Army Reserves. The rest of the year he was the starting long snapper for the University of Texas.

He is also 34 years old – self described as "too old and too slow." And oh, he never played high school football. He walked on at UT only five years ago on sort of a lark after he was enrolled following repeated frontline tours in the Iraq War.

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So after Texas' 2014 season ended, he decided to try out for the NFL, no matter how unlikely it seemed.

Boyer knew, at 5-foot-11, 220 pounds, he'd never be drafted. The end of that event Saturday, however, meant teams could start signing free agents for camp spots. This was going to be the moment. He just wanted some kind of a chance, even just an invite to an organized team activity. Thirty-four-year-old rookies can't be choosy.

And now the phone was buzzing with a strange number.

Seattle. The Seattle Seahawks. How many workouts or conversations had Nate Boyer had with them?

"None," he said before laughing.

Of course not. It didn't matter. General manager John Schneider and coach Pete Carroll were on the line. They were offering a contract and thus that chance to get to training camp. They were offering a path to the league.

"They just said they were excited to see me compete," Boyer told Yahoo Sports on Sunday. "I had spoken to a few other teams, but [not them]. I didn't know that I was on their list.

"It was the best kind of shock."

Boyer, whose military service ended in February, is but one player on a 90-man roster trying to find a way to survive until it's pared down to 53 on the eve of the season. There is no celebration here of making it because clearly nothing is guaranteed or even probable at this point. The odds remain long.

View photos Seattle long snapper Clint Gresham tweeted, Welcome to the squad! @NateBoyer37. (Getty Images) More

Clint Gresham has held the Seahawks' long snapping job since 2010 and was re-signed to a three-year deal in March. (Gresham graciously welcomed Boyer to the team on Twitter over the weekend.)

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