Fred Warner sat quietly in the 49ers locker room on Friday, seemingly insulated from the activity around him. His eyes were locked on a tablet displaying Kansas City Chiefs film. He scrolled back and forth, scanning the offense for tendencies and clues on how to defend it.

There were but a few moments between the time he plopped down and his weekly press conference, but he wasn’t letting spare seconds slip.

The 49ers middle linebacker clearly was taking advantage of every waking moment to prepare for Super Bowl LIV’s clash with the dynamic Chiefs attack.

All 49ers defenders will fine-tooth comb leading up to the championship game, as they have before each clash. It’s particularly important Warner understands what Chiefs coach Andy Reid’s offense can and will do, and how the 49ers' defense will respond.

The green dot demands it.

That indicates Warner is the 49ers' signal caller, relaying defensive coordinator Robert Saleh’s play calls to players on the field. He’s chiefly responsible for making checks and ensuring defenders are in proper position to make plays.

“I feel like it's an honor just to be able to be out there and have the green dot and give the calls,” Warner said. “I take a lot of pride in that, and I try and make sure I'm the most prepared every single week with my own preparation individually, outside of our meeting rooms and stuff like that, just making sure I'm watching tape.”

Just like he was in moments before uttering this quote Friday afternoon. Warner assumed the responsibility as a rookie last season and has grown into an adept field general capable of making sure the 49ers are in position to react quickly. He has been a rock in the middle, keeping the team's linebackers afloat this season after Kwon Alexander went down with a pectoral injury.

Warner has been excellent calling plays and executing them in his second professional season. He has 124 tackles, six passes defensed, a forced fumble and three tackles for loss in a year where he played 99 percent of all defensive snaps. He was even the NFL's Defensive Player of the Month in November.

Warner’s also in great sync with Saleh after nearly two seasons working with him.

“As a rookie, hadn't played in the box or even given calls before, so it was an adjustment for sure,” Warner said. “There was a learning curve. But this year, he's been great about just keeping up with me, just seeing where I'm at, if it's too much, and lightening the load for me so I can go out and just play fast and be able to anticipate what the offense is doing.”

Saleh talks extensively about removing gray area from his game plans, and taking some from Warner's plate, so his guys can react quickly and use immense talent to make plays. Reid’s offense can be complex, with ways to deceive defender’s eyes and make them a step slow. That’s death against Chiefs quarterback Patrick Mahomes and his track team of skill players.

“It's our job as coaches to try to make it ... you're always just trying to tell them a story and you’re trying to make it as easy as possible,” Saleh said. “You don't want to show them every play that coach Reid has run in the history of his system. You'd die, I think. But, at the same time you do have to -- coach Reid has a philosophy and we have to find a way to pull that out so the players can understand it.

“… It's our philosophy in this system to eliminate gray area from players, as much as you can. Gray area always creates hesitation. You want these players playing in a world of black and white so they know what's expected of them so they can go as fast as humanly possible.”

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Warner must have great understanding before the snap and relies on Saleh and extensive film study. He has grown to enjoy his homework and the mental side of a violent, yet cerebral game.

“That's something that for sure evolved over the years,” the BYU alum said. “[New England Patriots LB] Kyle Van Noy went to BYU and kind of took me under his wing, and he was a film junkie. I kind of took that from him. And then once you get to the NFL, it's a whole ‘nother ball game. You can't just go out there just hoping you're going to figure things out. You've got to be able to anticipate what's going on.

"You can't know that unless you're looking at the tape so you can see what they're giving you.”