By Dan Durkin-

INDIANAPOLIS (CBS) — Oregon’s Marcus Mariota is considered one of the top quarterback prospects in this year’s draft class and projects to be taken near the top of the first round. As he navigated through the barrage of questions like an incoming pass rush during his visit with the media Thursday at the NFL Combine, one question stopped him in his tracks.

Mariota was asked a question that seemed simple enough, one about what he felt the biggest transition was going to be for him from the collegiate game. After a measured pause, Mariota responded, “It’s going to be huddling.”

Other than the Philadelphia Eagles, who are coached by Mariota’s old college coach in Chip Kelly, huddling in the NFL is an assumption. While it seems like an inconsequential detail, it’s a big development for Mariota.

“There’s other things as well,” Mariota went on to explain. “In terms of, three-, five- and seven-step drops under center. But that’s all stuff that I’ve been able to work on in the last month and will continue to work on.”

Another top quarterback prospect, Baylor’s Bryce Petty, said that the Senior Bowl was the first time he’d experienced what a play-call was.

“It was a little different,” Petty said about receiving the play-calls during his week in Mobile. “We were a signal system at Baylor.”

Most collegiate teams aren’t running systems that will best prepare their players for playing at the next level. Instead, they’re installing schemes that they’re the most comfortable teaching and recruiting for. The NFL also doesn’t have a minor league system.

Thus, NFL terminology and in-game mechanics can be foreign to the top prospects at the most difficult position for NFL evaluators to scout.

In preparation for the draft, both Mariota and Petty mentioned they had been working with Kevin O’Connell to help flatten out their learning curves. O’Connell was recently named the Browns’ quarterbacks coach. Perhaps one of them will end up working with O’Connell again, as the Browns are in the market for a quarterback.

Mariota joins Petty in learning NFL lingo, which is a far cry from their recent run in college, which was characterized by plays signaled in via sideline posters or distilled down to a single number.

O’Connell gave Mariota an NFL play sheet to practice from as he familiarizes himself.

“He’s given me a play sheet and at night he tells me to just read the play calls out loud,” Mariota said. “That’s something little, but I think as this process goes, it’s going to help me with whatever team I get to, in terms of speaking in the huddle and articulating the play.”

Clearly, this highlights the challenges most young quarterbacks face as they transition to the professional level. Even so, Packers coach Mike McCarthy — who certainly knows a thing or two about elite NFL quarterback play — feels in many respects the new generation of quarterbacks are better prepared now than they were when he started in the league.

“There was a time that people felt that the shotgun, all this wide open offense would hinder a quarterback in the NFL, because you had to teach him to be under center,” McCarthy said. “The reality of it is, pressure, third down, key situational football is the biggest challenge for the young quarterback.

“These college programs have done an outstanding job of playing wide open and asking their quarterbacks to do more. I think they’re much better prepared from when I first got in the league. I think the transition for college quarterbacks coming in has been smoother, in my opinion.”

Dan Durkin covers the Bears for CBSChicago.com and is a frequent contributor to 670 The Score. Follow him on Twitter at @djdurkin.