MOBILE, Ala. -- Kyle Shanahan discreetly entered through a curtain that separates the quarterbacks meeting room from the linebackers. The 49ers coach pulled up a chair approximately an hour into the 90-minute meeting and quietly sat in the back right corner.

Shanahan delegated the responsibility of coaching the South team’s quarterbacks at this week's Senior Bowl to 49ers passing game coordinator Mike LaFleur. And in the makeshift meeting space at the Mobile Convention Center, LaFleur was surrounded by an intriguing mix of quarterback prospects: Will Grier (West Virginia), Jarrett Stidham (Auburn), Gardner Minshew (Washington State) and Tyree Jackson (Buffalo).

The 49ers granted NBC Sports Bay Area access to observe Thursday’s meeting, which began at 8:45 a.m.

After only about 10 minutes of watching film from the previous day’s practice, Shanahan was ready to move on and leave LaFleur alone to his eager students. But as Shanahan was exiting through the same opening in the partition, LaFleur turned and called to him.

“Are you sure you want to leave?” LaFleur said. “We’re going to do some board work.”

LaFleur said the words Shanahan apparently wanted to hear. Shanahan clearly was interested. He pivoted and returned to his seat.

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Stidham was called to the board to draw a play that he noted he had not run on the practice field. Stidham meticulously drew the play on the board.

 

“Against Cover-3, who will get the ball on this play?” Shanahan asked. Stidham answered correctly.

It was not long before Shanahan joined Stidham at the front of the room to take the instruction to another level.

Shanahan proceeded to go through a dizzying series of play variations with an answer for everything the defense might throw his way. After spending several minutes drawing on the board and listing a number of the scenarios Stidham could face, Shanahan cut to the bottom line.

“One of these guys is going to be open,” Shanahan said to Stidham. “But how quick can you process it?”

Players invited to the Senior Bowl are cramming for a test -- only they also are being graded daily even before the actual game arrives. While coaching the South team, the 49ers, along with 31 other NFL teams, are evaluating the prospects throughout the week on the practice field.

But, most important, the 49ers get an opportunity to see the players on the South team behind closed doors.

The college game has dramatically changed in the past decade, and no position has a steeper learning curve than quarterbacks when transitioning to the NFL. Shanahan said today’s quarterbacks generally are less advanced because they're asked to do fewer things at the college level.

“It depends on the schools and the stuff they run, but things have gotten so hurry-up, quick, and throwing bubble screens, and stuff like that, 80 plays in a game, defenses are just trying to get lined up,” Shanahan said. “So coverages don’t always matter.”

But quickly reacting to what the defense shows means a lot this week. And that process of teaching the quarterbacks is accelerated with a game to be played less than a week after arriving in town, surrounded by unfamiliar players and an NFL coaching staff. On Thursday, LaFleur and the four quarterbacks had their fourth meeting together. The emphasis was on installing the team's red-zone and two-minute offense.

Going up against an NFL defense considerably is more nuanced than what these players faced during their college careers. The players must take what they are taught in the meeting room to the practice field, then carry it over into game.

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“The good ones start to separate because they can do it so fast,” LaFleur said of the quarterbacks' ability to go through their progression on any given play.

 

LaFleur on Thursday installed just four red-zone plays, which can be run from any number of formations. Typically, the 49ers will carry 12 red-zone plays into a regular-season game plan. Shanahan will deligate play-calling duties for Saturday's game to LaFleur and run game coordinator Mike McDaniel.

After rising from his feet to ask Stidham some questions at the board, Shanahan took the marker and got going with a PhD-level dissertation of all the permutations from just one of those plays. Shanahan had everyone’s complete attention for several minutes.

“Everything he says makes complete sense,” Stidham said later. “It’s good to see him up there and going through it with us. And just to be with him on the board, and he’s hands-on, it’s really cool because I’ve never been drawing up on the white board with an NFL head coach.

"It was pretty cool. He’s got a great mind for football, and I’m just trying to learn as much as I can from him.”

Stidham has shown this week to be a quick study. During practice Wednesday, Grier made a common mistake as he took the first snaps among the group of quarterbacks. Grier took his drop too fast and was “a little ahead of the play,” LaFleur observed. Grier recognized the mistake. Stidham also was paying close attention as LaFleur interacted with Grier.

The same scenario presented itself to Stidham just a short time later. Having already recognized where Grier left room for improvement, Stidham slowed down his drop so he could hit the wide receiver in rhythm. LaFleur called it “an awesome rep.”

Said Stidham: “Any time the coach is talking to another quarterback, you got to open your ears and listen. I might not be there taking the rep, but mentally I’m taking the rep and I’m taking in anything he’s saying.”

It takes a lot of extra work to learn even the scaled-down version of the 49ers playbook that has been presented to the players this week. Minshew picked up the offense quicker than most with a little help from a friend.

Before arriving in Mobile, Minshew reached out to 49ers quarterback Nick Mullens, someone he has known for several years. He got a head start on some of the terminology and concepts he could expect this week. Minshew, the national leader in passing yards this season in coach Mike Leach's offense, is “all ball, all the time,” LaFleur said.

 

When LaFleur asked the quarterbacks about their confidence of being on the same page with the South wide receivers, Minshew’s delayed reaction prompted LaFleur to say, “You’re a little hesitant.”

Minshew responded his concerns were, “Not about me.”

Minshew is confident he knows and understands what already has been installed for practices and Saturday’s game. And if the wide receivers, tight ends and running backs spent as much extra time studying, they should be fine, too.

The 49ers consider themselves to be fine at quarterback for the 2019 season. Mullens, Jimmy Garoppolo and C.J. Beathard already are on their roster, so there might not be room to add a rookie quarterback to compete for a roster spot this year.

But 49ers general manager John Lynch believes learning more about the players in the room eventually could pay off at some point in the future, possibly in free agency.

“We’re spending a lot of time getting to know these quarterbacks and I think we feel pretty comfortable where we’re at with the quarterback position,” Lynch said. “But you do that for a multitude of reasons.

“No. 1, you never know what can transpire. No. 2, you want to get to know these guys for four or five years down the road. That’s just doing your due diligence.”