Manziel defies the typical mold of NFL QBs but could be a prized prospect as early as 2014. (US Presswire)

It probably seems a little early still, considering Johnny Manziel just finished his redshirt freshman season and has three full years of college eligibility left to burn. But so intense was Manziel's star in 2012 and so attractive is the lure of the next level that Texas A&M coaches are already beginning to prepare for life after Manziel -- and for the possibility that it might begin as soon as next year, when the reigning Heisman Trophy winner becomes eligible for the NFL Draft.

"With the uncertainty of Johnny's situation because of the way the NFL is going -- his stock is rising," newly promoted offensive coordinator Clarence McKinney told a group of A&M boosters in Houston earlier this week, according to the San Antonio Express-News. Because of that uncertainty, McKinney said, the addition of a pair of freshman quarterbacks last week was "huge" to the program's long-term fortunes.

"The way the NFL is going," of course, is toward an increased acceptance of mobile quarterbacks who challenge the defense as runners as well as passers, suddenly en vogue thanks to the immediate success of dual threats Colin Kaepernick, Robert Griffin III and Russell Wilson. Manziel led the SEC last year with 1,410 yards rushing -- including negative yardage on sacks -- and led all quarterbacks nationally with 21 rushing touchdowns. He went over 100 yards on the ground in eight games, capped by a 229-yard romp through a confused, overmatched outfit posing as Oklahoma's defense in the Cotton Bowl.

Traditionally, the NFL is wary of college scramblers, especially ones barely scraping six-feet tall. (Of 35 pro quarterbacks who attempted at least 200 passes last year, all but three -- Wilson, Drew Brees and Michael Vick -- are listed at 6-foot-2 or taller; Texas A&M lists Manziel at 6-1, 200 pounds.) With the increased emphasis on athleticism, though, along with the fact that Manziel also passed for 3,706 yards and 26 touchdowns as a first-year starter, there will be plenty of interest whenever he decides to make the leap.

Because he enrolled at A&M a semester early, in January 2011, Manziel is also well on his way to a degree. Depending on how far the Aggies go in 2013 toward claiming an SEC or BCS championship, by the time the 2014 NFL Draft rolls around, there might be nothing left for him to prove on campus.

Davis might be second-string. (247Sports)

The incoming recruiting class includes a pair of four-star quarterbacks, Kenny Hill and Kohl Stewart, who are scheduled to join holdovers Matt Davis and Matt Joeckel in a four-way battle for the right to serve as Manziel's understudy this fall. (Last year's top backup, Jameill Showers, is already making plans to transfer in pursuit of playing time.) Stewart, a 6-foot-3, 190-pound fireballer with a 95-mph fastball, is also considered one of the nation's top high school pitchers, and a potential first-round pick in this summer's MLB Draft. If so, the opportunity and guaranteed six-figure signing bonus that comes with it could make a pro baseball career too tempting to pass up.

In the meantime, first crack at the backup role likely belongs to Davis, who has all four years of eligibility remaining and a spring practice and a redshirt season already under his belt. "[Davis] took every snap on our scout team," McKinney said in Houston. "He's learning how to run our offense right now. When Johnny leaves, he's going to be right there in the competition to take over the spot."

Still, for another year, at least, Manziel is the sun around which everything else in the Aggie universe revolves. And the prospect of it being his last only increases the pressure to make it count. If he manages to replicate the once-in-a-lifetime numbers that propelled him to stardom, it will rank among the great individual feats in the history of the sport. But the next line on his résumé is reserved for championships only.