We've had two straight Heisman-winning quarterbacks who had never played a down in college football at this point in their award-winning season. With that unprecedented success, it's no wonder that people are more and more interested in spotting the next unexpected breakout star under center. While there may not be another Manziel this year who comes from absolutely nowhere to become a megastar, there are some quarterbacks with limited experience and little current exposure who could rise up to deliver some nice value for bettors.

Here are five that stand out:

Jacoby Brissett, N.C. State Wolfpack: Brissett is a redshirt junior who will be seeing his first game action this year since 2012 because he transferred from Florida. The coaching staff is very high on him. Really, his timing is pretty good - Dave Doeren had a lot of changes to make when he took over in 2012, so Brissett takes over a more stable program than the one he joined. There is a story about Brissett that is getting a lot of traction, and it's a good one. Redshirted players do not go on road trips, but Brissett wanted to be a part of the team so much that he drove himself to all but one game. If he can bring that level of commitment to his game then that combined with his natural talent could really make things interesting.

Will Gardner, Louisville Cardinals: Gardner is at the eye of a whole lot of upheaval in the Louisville program. Teddy Bridgewater is with the Vikings now. Charlie Strong is out, and Bobby Petrino is, bizarrely and controversially, back in charge. The team has now joined the ACC. Given all that, it would be understandable for Gardner and the Cardinals to struggle this year. The program didn't bring Petrino in to rebuild, though, and Gardner gives the team some real hope. His experience last year as a freshman was very limited, but it was nonetheless impressive - he completed 8-of-12 passes and tossed two touchdowns. He also had an incredibly impressive showing in the team's spring game this year with more than 500 yards.

Hutson Mason, Georgia Bulldogs: It's an unenviable task to take over for a legend like Aaron Murray. Mason knows better than anyone what he is taking over, though - the redshirt senior was behind Murray all of the last four years. He got his chance to start a couple of games last year, including the bowl game, when Murray was hurt, so he has some game experience and confidence. Combine that experience with his maturity and the wisdom gained from working so closely with such a successful college quarterback and he could put together a strong season. The biggest concern here is also the biggest opportunity to make a real strong early impression - his first two games this year are at home against Clemson and then at South Carolina. If he shines through that gauntlet then the residents of Athens might forget who Aaron Murray was. It's worth noting that coach Mark Richt has been through this same situation before and had great success - D.J. Shockley had to wait behind David Greene before shining in his senior season as starter.

DeShaun Watson, Clemson: Watson is the only true freshman on this list, and he is the only one who isn't likely to be the opening-day starter for his team. He also has the highest upside of the group. Watson is a true freak, and he is the centerpiece of the most recent recruiting class for the Tigers. He will see the field at least a little bit during the opener against Georgia, and it is just a matter of time before he takes over starting duties on a full-time basis. He is a dual-threat quarterback who absolutely torched his competition is high school - and that was in Gainesville, so it's a coup that Clemson landed him over the Gators. Watson has been very impressive leading up to the season, and chances are very good that people will be talking about him a whole lot more heading into next season than they are now.

Patrick Towles, Kentucky Wildcats: The Wildcats were just plain incompetent on offense last year, but Towles could start to lead them out of the dark. Before last season the Wildcats lured offensive coordinator Neal Brown from Texas Tech to install a version of the air raid offense. It didn't go well at all last year, but thing should be more impressive this year, and Towles has the tools to make things work. Towles saw limited action as a true freshman, but he redshirted last year to work on fundamentals - an investment in time that has paid off as he won the starting gig and could pay off even more once he hits the field.

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