Potential top-five NFL draft pick Trey Lance was smart to host two pro days, because he is one of the most mysterious first-round-caliber quarterback prospects of the 21st century.

For those considering drafting the North Dakota State product next Thursday, the circumstances are unprecedented.

In summary:

• Lance is the only highly-rated quarterback in this class who is coming out of the Football Championship Subdivision.
• He's also the only highly-rated quarterback in this class who didn't participate in a competitive season in 2020 since the Bison postponed their campaign because of the COVID-19 pandemic.
• Even prior to that, Lance had thrown just 288 passes and was a one-year starter. Mike Renner of Pro Football Focus notes his 319 total college attempts rank lowest among all quarterbacks in this class, and by a wide margin. 
• The Ringer's Danny Kelly points out that he also threw just 113 passes in high school.
• His one appearance in 2020—an October game against Central Arkansas—was not as crisp or impressive as most of his 2019 performances. He completed just 15 of 30 passes and threw the only interception of his college career.
• NFL scouts and talent evaluators were not able to meet and analyze him at the Scouting Combine, which also didn't take place in its usual form because of the pandemic. This was the case for every member of the draft class, but it took away a chance for executives to catch up on Lance.
• Also because of the pandemic, there were no private workouts during this predraft process.
• Still just 20, Lance is raw.

Lance has been compared to a variety of current and former NFL quarterbacks, from Michael Vick to Cam Newton to Lamar Jackson, Josh Allen, Andrew Luck and Matthew Stafford. That shows how gifted he is, but it also indicates how much more the seed has to sprout.

At 6'4", 224 pounds with 4.5-second 40-yard dash speed, Lance could blossom as a playmaker coming from a pro-style system. He's a big-armed prospect with elite mobility and top decision-making skills.

But how long will that take, and what will the final product look like? Consider that about half of the signal-callers selected in Round 1 become busts, and it's easy to see why quarterback-needy teams with primo draft picks—such as the San Francisco 49ers, Atlanta Falcons, Denver Broncos and New England Patriots—are at least performing their due diligence.

Those four squads were to be represented at Lance's second pro day Monday, according to NFL Network's Ian Rapoport, who reported that general manager John Lynch and head coach Kyle Shanahan were expected to be present for the 49ers.

With Trevor Lawrence of Clemson and Zach Wilson of BYU almost certain to be drafted first and second by the Jacksonville Jaguars and New York Jets, the 49ers are likely in the driver's seat after their trade into the No. 3 spot. Barring something unforeseen, they will draft Lance, Justin Fields of Ohio State or Mac Jones of Alabama.

Beyond that, the Falcons could pick veteran Matt Ryan's heir apparent at No. 4, the Detroit Lions may be tempted by a quarterback at No. 7, and the Broncos will choose at No. 9. The Philadelphia Eagles (No. 12), Minnesota Vikings (No. 14), Patriots (No. 15), Washington Football Team (No. 19) and Chicago Bears (No. 20) are wild cards outside the top 10.

Any of those teams would likely have to trade up for Lance, which would represent a tremendous gamble considering his resume. He may have thrown 28 touchdown passes to zero interceptions while also rushing for 1,100 yards and 14 touchdowns in 2019, but that was his only college season, it took place more than a year ago, and it wasn't in the Football Bowl Subdivision. Plus, his completion percentage (66.9) and yards-per-attempt average (9.7) weren't as jaw-dropping.

That last factor is likely less daunting to potential suitors thanks to the recent success enjoyed by small-program products such as Allen (the reigning MVP runner-up didn't play in the Power Five but for Wyoming), Carson Wentz (the 2017 MVP candidate is also a North Dakota State alumnus) and Jimmy Garoppolo (Lance might eventually replace him, but the Eastern Illinois product helped get the 49ers to the Super Bowl two seasons ago).

Prior to that, Tony Romo also came out of Eastern Illinois, Steve McNair excelled out of Alcorn State, Kurt Warner was great after he played for Northern Iowa, and Joe Flacco and Rich Gannon succeeded as Delaware alumni.

Still, it's a big reason Lance remains an unknown.

San Francisco and other quarterback-starved squads have been represented at pro days for other quarterback prospects as well, but ESPN's Dan Graziano reported the Niners would be "extremely involved" in Lance's final workout.

"Lance, who works with QB coach Quincy Avery, spent the past couple of weeks working with QB coach John Beck. Kyle Shanahan coached Beck in Washington a decade ago and trusts his opinion," Graziano added. "I'm told Lance went to work with Beck at Shanahan's request, and that the Niners' coaching staff gave Beck a list of drills they wanted Lance to work on ahead of Monday's workout. Effectively, the 49ers designed the workout and will have a hand in administering it."

That doesn't mean the 49ers will draft Lance, but that'd be one hell of a smokescreen. And while it's understandable they'd be intrigued by Lance, San Francisco would be taking one of the largest gambles in draft history.

Don't forget that the 49ers traded up, which yours truly established last week is almost always a bad idea: "A team has never traded into the top five and landed a quarterback who became its primary starter for more than six years."

If the 49ers walked away from Lance's second pro day—which was also the last pro day for any of the quarterbacks expected to be selected in Round 1—satisfied, they could be just days away from spending three first-round picks as well as a third-round selection on a player who has started just 17 games against FCS competition.

It's possible Lynch and Shanahan are convinced that seed will become a beautiful orchid, and it's also possible they're right. But that doesn't change the fact that there's guesswork involved and that teams with a chance to pick Lance have less to work with than usual when making that guess.

Lance's physical features are hard to deny, though, and his 2019 numbers were remarkable regardless of the competition.

Someone will gamble, and ideally that someone will have patience. And then we'll collectively watch to see how the seed grows. It's the beauty of the draft.

Brad Gagnon has covered the NFL for Bleacher Report since 2012. Follow him on Twitter, @Brad_Gagnon.