We all know Case Keenum is a workhorse.

First guy in, last guy out, film-room junkie, a work ethic that’s second to none, etc., etc. It’s something that has been well-documented by his coaches and teammates, both current and former. The quarterback’s meticulous attention to detail and tireless preparation isn’t something he takes lightly. He said so himself just about every time he was asked this season how he stayed sharp during a period when it wasn’t exactly clear how long he would remain the starter.

This season, Keenum found a way to get the most out his time every week, particularly when he’s not getting live reps or in the quarterback room.

That method is virtual reality. Like many teams across the NFL and in college football, the Minnesota Vikings use technology patented by STRIVR, an industry leader in virtual reality training. Back in the spring, when Keenum was a new addition to the Vikings' roster as a backup, general manager Rick Spielman and offensive coordinator Pat Shurmur sat down with him and the other quarterbacks to find out if VR was something they wanted to incorporate in their routines. According to CEO Derek Belch, Keenum had seen STRIVR’s demo when he was with the Rams and decided it would be beneficial to work into his prep beginning in organized team activities and mini-camp.

That was at a time when he wasn’t getting first-team reps, but even after Sam Bradford went down and the Vikings turned to Keenum, the quarterback chose to stick with VR.

“A lot of guys who are starters don’t think they need it anymore because they’re getting reps on the field,” Belch said. “[Keenum] said, ‘No, I think this is something that would be even more valuable as a starter as a supplemental preparation tool.’”

As a result, Keenum has had thousands of additional mental reps. In total since he took over starting duties in Week 2, Keenum has viewed 2,647 plays through virtual reality, which translated to him getting to review every play the Vikings have run this season two to three times from a mental standpoint over the course of the year, according to STRIVR’s tracking data.

All of that has added up to hours of cumulative mental practice on top of what he’s doing physically.

Belch is quick to note that STRIVR can’t be credited for a player’s performance, but he points to compelling data the company has tracked on players who have used the technology and had the best years of their career.

Take, for example, how well Keenum has performed under pressure this season. His 59 QBR when pressured was the highest in the NFL, as was his 88 QBR when facing a blitz, according to ESPN Stats & Information research.

Could that be the result of his VR training?

Oftentimes teams will stop practice and do walk-throughs to choreograph what they want to see in building a library for their quarterbacks. The cumulative effect of those mental reps, in which a quarterback may see the same play in virtual reality five, six or seven times, is something Belch measured when he developed STRIVR as a graduate assistant coach at Stanford three years ago while working with former Cardinal quarterback Kevin Hogan.

“The tendency for a quarterback against the blitz is to speed up when he sees the blitz coming when, in reality, he needs to slow down,” Belch said. “I know it’s only fractions of a second. He needs to say, ‘Where do I need to go? What do I need to do to not make a hurried decision?’ I think seeing these reps again and again in VR helps these guys do that.

“[Hogan] told me, ‘The game is moving slower, I’m more confident on the field, I know when Notre Dame is blitzing me. It’s a joke how easy it is for me to see it coming because I saw it 30 times during the week in addition to what we did on the field.’”

Keenum has been what Belch calls a model user of STRIVR’s technology. At the end of each week, the quarterback goes in to Minnesota’s VR room at the practice facility to do a touch-up review and his last-minute checklist on a handful of the Vikings' passing and blitz concepts. Over the course of 20 to 25 minutes, he’s able to comb through a few hundred reps as part of his final preparation.

Hours of additional work aside, nothing can replicate the experience Keenum has derived from this season from the snaps he takes in games. Still, as some expected Keenum to cool off after a while, the quarterback managed to maintain his success throughout his 11-3 record as a starter.

“He’s getting better, not getting worse, because he’s putting more work in and getting more comfortable every week in their system,” Belch said. “Carson Palmer, Tony Romo, guys [STRIVR has worked with] in veteran systems, they were like, ‘Man, I wish I had this when I was a rookie because it took me three years to get comfortable in the offense.’ He’s had less than one year to learn an entire offense and it’s turned out really well.

“The effect on your brain says this [technology] is legit. Having the headset on is more effective that 2-D learning. This stuff works when people buy in and do it right.”

The Case Files: Each day leading into the Minnesota Vikings' divisional-round matchup, get to know more about Minnesota quarterback Case Keenum with a series of stories told by those who have been part of his journey. Monday: The inner kid and a life-long friendship