Jameis Winston and Marcus Mariota are locks to be the top two quarterbacks off the board on Thursday night, and most likely will be the top-two picks in the draft. This duo has gotten the lion’s share of coverage for the quarterback class this year, but there are, in fact, a few other intriguing prospects at the position. Baylor’s Bryce Petty, UCLA’s Brett Hundley and Colorado State’s Garrett Grayson comprise that “second tier” in my mind, that could challenge for backup roles in the pros, or even surprise some and win a starting job down the line.

The spread quarterbacks

One common theme that kept coming up among general managers and coaches at the NFL Combine in February was the difficulty in evaluating college quarterbacks these days. With the prevalence of the spread system in the NCAA, quarterbacking skills and attributes are harder to project at the pro level, and players come out of the college ranks lacking basic fundamentals and experience doing what they’ll be asked to do with their new teams.

The simple task of taking snaps from under center; the precision footwork involved with three-, five- and seven-step drops … things that most fans take for granted — like learning to adjust to completely turning your back to the defense to perform a play-action fake come into question. This extra second or two of time with your eyes off the defense can make a major impact in identifying the coverage and reads, and can be a hard thing to quickly pick up, particularly against defenses with effective scheme-masking and with NFL speed.

Some college quarterbacks do not even read defenses in the pre-snap phase, instead looking to the sideline after getting set to wait for the coach on the sideline to adjust. They can have one defined read in their play and in many cases, the ball comes out very quickly. These are the challenges, and it makes an already difficult job — evaluating quarterbacks — even harder.

The second tier is made up of two spread quarterbacks and a “pro-style” signal caller. Let’s look at the spread guys first.

Bryce Petty, Baylor

Strengths: Petty looks the part as a pro-style thrower and whips an effortless deep ball down the field. He’s athletic enough to move around behind the line and reset to make throws, and he can be tough to bring down on scrambles and designed runs. He he has a nose for the end zone on these plays as well (21 career rushing touchdowns). His statistics are very strong over the past two years — 4,200 yards passing (62 percent complete) with 32 touchdowns to three interceptions in 2013, and 3,800 yards passing (63 percent) with 36 touchdown passes to seven interceptions in 2014. Naturally, the fear is that these gaudy numbers were propped up due to his one-read quick-throw spread system at Baylor, but you can’t completely discount how effectively and consistently he produced in it either.

He protects the football by leading his receivers downfield and not giving defenders a chance on the ball. Of course, this could be considered a weakness (inaccuracy), depending on your point of view. That leads me to …

Weaknesses: He will overthrow his receivers downfield, even when they have a good amount of separation. All of his weaknesses as a quarterback relate directly to the offensive system that he operated in — with quick throws and pre-determined reads, there are major question marks about his ability to run a pro-style, under-center offense. His pocket poise, reactions to pressure, ability to read defenses, go through progressions — all these are concerns.

Overview: Petty has excellent quarterback size at 6’3, 230 pounds, with a strong arm and big hands (10″), and he’s above average in athleticism (registered a 34-inch vert, a sub-7.0 three-cone, and a 4.12 short shuttle at the Combine). So, he has the tools that all NFL GMs look for at that position and while he’s a project based on the college offense he ran at Baylor, I’m guessing a lot of people will see a guy that they can mold and develop with an early-mid round pick. He’s already 24, so that’s a knock on him — he’s no Brandon Weeden, of course — but for a guy that probably needs two years to learn the pro-style offense, it’s a risk.

He’ll need time to nail down the footwork and progression reading of a pro-style offense in order to develop into a viable starter (or more likely a strong backup), but definitely has that upside. Additionally, and this is just based on reading scouting reports from around the web, he’s known to be a gritty competitor and leader that played through injuries (a back injury and rib injury), so that gives him an edge in the intangibles department.

Brett Hundley, UCLA

Strengths: Hundley does a very good job of manipulating the defense with his helmet when taking the snap and getting into his read — he’ll look right before coming to his target on the left and visa versa. He’ll wait until the last second to lock onto his receiver and make the throw. This will be hugely important in the NFL. He throws a crisp, accurate back-shoulder corner-ball. He can spin the football downfield with apparent ease and has good arm strength for the NFL. He has a calm demeanor in the pocket (to his detriment, at times, more on that in a moment).

He’s a very strong, fast runner in the open field and if he gets a head of steam can outrun defenders. He’s got great size at 6’3, 226 pounds with 10 1/4″ hands and based on reports is a strong leader and tough player. He started all 40 games he played in in his career and was voted a team captain his sophomore season. He could be used in a read-option heavy offense as a backup early in his career because of his great athleticism and experience there.

Weaknesses: There are times where, despite his obvious arm strength, his deep ball can hang up and slow down on the back end and die — perhaps due to putting a little too much vertical trajectory on the ball. This may be related to one issue that he’s been docked for — his inaccuracy passing the football. Touch isn’t his strong suit at this point, and it’s an issue on passes down the field. One other area of concern that I had when watching his tape was that he tends to carry the ball a little low against his body when in the pocket. I noticed it starts up high at the beginning of the game but tends to come down as he gets further along and ends up below chest level at times. This can make him have a more elongated wind-up and slows his release. It probably doesn’t help with ball security (he’s fumbled 29 times in three seasons) either.

Hundley has amazing open field prowess as a runner but despite his top-tier athleticism for the position, doesn’t really display great pocket movement or a natural ability to slide around to buy time and avoid the rush. In the games I watched, he took a lot of sacks that a “mobile” quarterback should probably be able to escape, and even when he appears to see the pressure coming directly at him, he is late to react and can’t avoid it.

Overview: The UCLA offense features a lot of shotgun read option package plays, so you see a lot of screen passes behind the line of scrimmage and almost all of his snaps are in shotgun. Hundley, like a few other quarterbacks in this class, is a toolsy athlete that some team will take and hope to develop into a more consistently accurate passer. He has the size, speed, and arm strength, though, so don’t be surprised to see him end up in a vertical passing offense with an already established starter — he could be groomed to become a top-end backup or potentially even a starter down the line.

The pro-style quarterback

When I say pro-style quarterbacks, the things I look for in their games are the ability to take snaps from all three platforms — in shotgun, in pistol, and under center. They make checks at the line of scrimmage. They’re reading defenses. They’re going through progressions at times. These attributes, in some form, were displayed by the following quarterback.

Garrent Grayson, Colorado State

Strengths: Grayson does a great job of sticking in the pocket even in the face of pressure. He’s not afraid to hang in there, climb away from the rush and keep his eyes downfield the whole time. He’s used to operating under center and in play-action with his back to the defense, and the Colorado State offense asks him to throw on bootlegs fairly often. On those plays, he throws well on the move, both to the left and to the right. He’s smart — there were multiple instances where instead of throwing the ball into a well-defended window, he instead throws the ball away. He’s not a burner like Marcus Mariota, but he’s relatively athletic for the quarterback spot and can escape pressure if he needs to. He shows a willingness to throw into tight windows over the middle — he’s relatively fearless, in fact — and combined with his low interception totals from this past year, that’s a good combination of chutzpah and accuracy.

From everything I’ve heard and read on him, he’s got excellent off-field intangibles and is a hard worker, dedicated to his craft.

Weaknesses: Grayson lacks velocity on some passes that go across the field or down field. He has a big enough arm for the NFL but I wouldn’t say it looks effortless when he chucks it deep or tries to put some mustard on it. He throws off balance or off his back foot at times when his offensive line is encroaching on his spot. I have no idea how he’s coached on this at Colorado State, but he tends to open his hips immediately upon getting the ball when he’s throwing left — and stays there until he releases it — and this could be something that safeties and corners will more easily read at the next level. He can lock onto his target at times. Needs to refine his ability to move and hold defenders with his helmet and with his body posture.

Overview: Grayson is slightly undersized but makes up for it with his ability to function in a muddied pocket. He’s better than any of the other second-tier quarterbacks at keeping his eyes downfield while avoiding the rush and climbing the ladder to make a throw. He’ll make throws while “staring down the gun barrel” but at times he looks off-balance in doing so. He doesn’t have some of the tools that the other quarterbacks in this class have, but I’d say he’s more refined and ready to step into a role as a backup immediately. He has the poise and confidence you look for in that role, and could develop into starter-caliber down the line.

SB Nation presents: Final mock draft before the real thing on Thursday