(For all Inside Slant posts, follow this link.)

EDEN PRAIRIE, Minn. -- Earlier this month, Taylor Heinicke stepped into a group of 10 other NFL rookies and called a play. When he was finished, his teammates clapped their hands once and jogged to the line of scrimmage. Heinicke positioned himself behind the center, extended his arms, inverted one hand atop the other, called out more signals and received the snap.

Heinicke, a quarterback hoping to earn a spot on the Minnesota Vikings' roster, was administering the traditional pre-play routine for essentially the first time since his junior year in high school. In a scene playing out around NFL rookie camps and organized team activities (OTAs), he is attempting to transition from a pure spread offense to the hybrid scheme most teams are running -- one that calls for huddles and at least some under-center snaps.

The Vikings' interest in Heinicke, an earnest prospect with few conventional credentials, helps illustrate the supply shortage and accompanying predicament pro teams are facing.

Only seven quarterbacks were drafted this year, the fewest since 1955, as league executives feel their way through the challenges posed by the spread's proliferation. Still, there remain roughly 96 roster spots available to quarterbacks, forcing teams into new levels of projection and out-of-the box thinking to find suitable depth.

"If you just eliminate the spread quarterbacks because of the offense they play, you're going to miss out on a lot of good players," said Vikings quarterbacks coach Scott Turner. "Because so many people are running that offense and it's not changing. I don't think anyone is going to tell Baylor that their offense is bad when they're scoring 55 points a game. So you've got to go work these guys out."

Heinicke put up big numbers at Old Dominion University, throwing for 14,959 yards and 132 touchdowns in 46 games as the school moved from FCS to FBS affiliation. But he wasn't invited to the NFL scouting combine and produced an uneven 2-for-9 performance in the East-West Shrine game, generating questions about both his size (6-foot-1, at least officially) and arm strength.

It's not unusual for a short and weak-armed quarterback from a low-level school that played in a non-transferrable scheme to receive middling attention from the NFL. Historically, quarterbacks with that profile have little chance to make a team. In 2015, however, the playing field has been leveled. It's a race: The first one to make the transition from the spread offense wins, and the Vikings want to find out if Heinicke can do it. They enticed him with a $20,000 guarantee -- about the highest most teams can go for undrafted free agents -- to sign and will give him a full opportunity to earn a spot behind starter Teddy Bridgewater and backup Shaun Hill.

"To me it's a combination," Heinicke said. "Some pro teams are being more flexible with the spread guys. You're seeing a lot of them in the shotgun more often. Then, I think with kids coming in, it's just a matter of how fast you can adapt. I really don't know how it will go, but that's just my perception of the situation."

Indeed, NFL teams used the shotgun on 59.9 percent of plays last season. Even the Vikings, who run a traditional three-digit passing scheme, were at 64.2 percent. But that is among the few concessions NFL teams can make to most versions of the college spread, given the physical dangers of giving quarterbacks a run option and the complexity necessary in passing schemes to compete with pro-level defenses.

As we've discussed before, the league is facing a crossroads at the position. It must either find a way to convert spread quarterbacks or simply give in, run the scheme and have depth on hand to deal with the injuries it likely would create.

For now, the job rests with coaches like Turner, who liked what he saw in Heinicke's college film and is willing to give him a shot.

"The one thing with the spread offense, especially the spread passing offense, is you get to see the guys throw," Turner said. "A lot. Maybe the footwork isn't the same, or maybe the way you read a play is different, but the ability to throw the ball, to get in that work, is there. As long as that's the case, I think you're going to continue to have good players."

It starts, naturally, with the huddle and snap. Heinicke prepares for it by repeating the routine 50 times during every training day. Welcome to NFL quarterback development, circa 2015.