Three years ago, three Alabama high school quarterbacks signed with SEC programs.

Last year, three more Alabama high school quarterbacks signed with Power 5 teams.

This year, five quarterbacks have already committed to SEC programs -- Thompson's Taulia Tagovailoa and Hewitt-Trussville's Paul Tyson to Alabama, Pinson Valley's Bo Nix to Auburn, James Clemens' Jamil Muhammad to Vanderbilt and Central-Phenix City's Peter Parrish to LSU. McGill-Toolen's Sheldon Layman has committed to Memphis.

Alabama long ago earned a reputation for producing plenty of college signees, but quarterback hasn't always been the state's top crop.

"The value of a dynamic quarterback is as high as it's ever been," said 247sports recruiting analyst John Garcia. "Coaches want that."

But why has Alabama suddenly begun producing so many quarterbacks? High school coaches and recruiting analysts agree the proliferation of the spread offense and the trickle-up of spread concepts becoming increasingly prevalent in the college game explains it.

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When Rush Propst arrived at Hoover nearly 20 years ago, most Alabama high schools relied on the wing-T and other run-heavy offenses influenced by Pat Dye's Auburn success in the 1980s and Bear Bryant's wishbone-fueled championship run of the 1970s.

In 1995, for instance, Central-Tuscaloosa won the Class 6A title with the practically ancient Notre Dame Box installed by coach Howard "Buzz" Busby.

Everything changed when Propst got to Hoover.

Propst wasn't the first to uses a pass-happy philosophy. Barry Halladay did it at Minor before winning a state title at Anniston, Joey Jones did it at Dora and Mountain Brook, and Dan Hogan threw it around at Lynn and Winston County, but they were outliers who used multiple receivers and embraced the passing game.

Propst changed the game by winning at Hoover with offense and averaging at least 32 points per game during his championship stretch from 2001-06.

"I remember running into a lady in the grocery store and she said, 'Are you going to run it, run it, run it and punt it?" Propst said. "I laughed and said, 'No, ma'am, we'll be exciting if nothing else.'"

Growing quarterbacks

As the spread offense spread, the state began producing quarterbacks.

At Williamson in Mobile, JaMarcus Russell led his team to a state title-game appearance as a freshman and threw for more than 10,000 career yards before becoming the NFL's overall No. 1 draft choice in 2007. Chris Smelley came along a at American Christian and also threw for more than 10,000 yards before signing with Alabama.

Alabama and Auburn recruited Phillip Rivers as an athlete, but he signed to play quarterback at North Carolina State out of Athens and has now thrown for more than 50,000 yards in the NFL.

Daphne's Pat White led the Trojans to the 2003 Class 6A title game, falling to Hoover and Propst, and later led West Virginia to four straight bowl wins and set an NCAA record for career rushing yards for a quarterback.

Mobile's AJ McCarron signed with Alabama in 2009 and led the Crimson Tide to two national championships. He's now in his fifth season in the NFL.

Jameis Winston starred at Hueytown and finished runner-up to Daphne running back T.J. Yeldon in the 2011 Mr. Football balloting. He went on to become a Heisman Trophy winner at Florida State and became the NFL's overall No. 1 draft pick by the Tampa Bay Bucs in 2015.

Most of those players played in a spread offense, which allowed them to showcase their passing skills for college scouts.

"Football is evolving," said Thompson coach Mark Freeman, a split-back veer quarterback in high school who helped current UAB quarterback Tyler Johnston win Mr. Football and now tutors Tagavailoa. "I grew up on Bear Bryant, just line up and whip people. Now to be successful, you have to throw it around a little bit."

Spread produces QBs

As more and more teams adopted the spread offense, 7-on-7 summer tournaments grew.

The AHSAA relaxed its rules on summer practice and essentially endorsed 7-on-7 play, a move allowing more 1-on-1 summer instruction of quarterbacks. That led, coaches say, to rapid quarterback development.

Propst estimated most high schools' summer workouts now equate to another 30 practices, just without pads or tackling. "It made football in the summer fun," he said. "You could say 7-on-7 made football fun for in the summer for the skill athlete."

Over the course of a high school quarterback's career, the additional summer work translates to at least 100 additional practices. For quarterbacks, that means plenty of extra time to enhance mechanics and football IQ.

"These kids are getting coached at a younger age, and high school coaches are better than they've ever been," said former Ole Miss quarterback David Morris, founder of the QB Country program.

As 7-on-7 and practice time grew, coaches began putting more responsibility on quarterbacks for pre-snap reads and at-the-line decision-making. That, in turn, made Alabama quarterbacks more attractive to college coaches.

"There's stuff I talk to our quarterbacks about now that would have been like French or Spanish to me back in the 1990s," said Hoover coach Josh Niblett, a high school quarterback.

Added Propst, "There's no doubt we put more on high school quarterbacks with run progressions and sight adjustments and things you never thought a high school quarterback could do, and he's doing it in the 10th and 11th grade."

As college coaches took notice, quarterbacks began seeking more specialized 1-on-1 training such as QB Country, which started in Mobile and now has expanded to Mississippi, North Carolina, Texas, Georgia and Tennessee.

"Quarterback gurus are everywhere," Propst said.

Athletes playing QB

The spread's reliance on the quarterback as a runner and passer also means some players who would have played another position -- like receiver or defensive back -- are now targeted to play quarterback.

As spread concepts filter into youth leagues, dynamic athletes who once played I-tailback now spend their whole lives at quarterback.

"It's all relative," said Pinson Valley coach Patrick Nix, who has coached his son Bo throughout his high school career. "Twenty-five to 30 years ago, there was no spread in college. They wanted bigger pocket passers. The college game now has a lot of quarterbacks who would have been playing receiver or defensive back now getting the chance to play quarterback. ... The college game evolved to more athletic quarterbacks."

Not all high school spread quarterbacks, of course, stay at the position in college. Blount quarterback Kadarius Toney signed with Florida in 2017 and was promptly moved to receiver, and Park Crossing quarterback Cam Taylor signed with Nebraska and quickly transitioned to cornerback.

But the numbers don't lie. Five former Alabama high school quarterbacks are currently in the NFL -- Rivers, Winston, McCarron, Wenonah's Joe Webb and Spain Park's Nick Mullens. Mullens is on the 49ers practice squad.

South Carolina quarterback Jake Bentley prepped at Opelika, while Alabama, Auburn, Arkansas and Texas A&M have former Alabama HS stars in back-up quarterback roles. Brantley's Jacob Free left Vanderbilt after a season and now plays in junior college, and Saraland's Jack West is a freshman back-up at Stanford.

The recent quarterback crop also included McGill-Toolen's Bubba Thompson, a first-round pick in the MLB Draft who was offered as a quarterback by Tennessee and a long list of smaller schools.

Hewitt-Trussville's Zac Thomas nearly led Appalachian State to a season-opening upset of Penn State, and Priceville's Kaleb Barker won the starting job at Troy. Barker replaced Gulf Shores' Brandon Silvers, who threw for a school-record 10,677 yards a four-year starter for the Trojans.

At Samford, Mortimer Jordan's Delvin Hodges has already thrown for more than 10,000 yards in three seasons and has a chance to break Steve McNair's Football Championship Subdivision career passing record this season.

"You see guys like Zac Thomas and Delvin Hodges, that's a sign of the strength of the state," Garcia said.

Don't expect it to stop with the star-studded 2019 class of Tagovailoa, Nix and Tyson.

Hoover's Robby Ashford ranks among the nation's top dual-threat quarterback prospects in the Class of 2020, while Athens junior Logan Smothers has committed to Nebraska. Bob Jones' Caden Rose, Saraland's Brett Nezat, Spanish Fort's Jackson Burkhalter and Central-Phenix City's Tucker Melton -- all juniors -- have already drawn the attention of major college scouts.

Josh Bean covers high school sports for AL.com. He can be reached at jbean@al.com.