The move was made on an experimental basis , but Vikings coach Leslie Frazier said he wants to incorporate Griffen as a linebacker into some special defensive packages.
"We have some packages where we want him to stand up sometimes and we thought this would give him an opportunity to get comfortable doing that when we go to some of those packages during the course of the year," Frazier said.
They hope to incorporate him into the position during Thursday's fourth preseason game against the Houston Texans.
"It was my first day out, so I'm going to get after it tomorrow when we get more base calls in and I get in the book with Coach Singletary a little more. I've just got to go out there and get the job done," Griffen said.
The 2010 fourth-round draft pick came in during his day off Sunday and found out about the switch then, which was made at least in part because of the Vikings' thin numbers at linebacker. After injuries last week that limited Heath Farwell (hamstring), Jasper Brinkley (hip), Kenny Onatolu (foot) and Ross Homan (concussion), the Vikings were getting desperate at linebacker and signed Kyle O'Donnell (released Monday) and David Herron as reinforcements.
But Griffen does have something to add to the equation.
"He's a tremendous athlete," Frazier said. "A guy that weighs 270 pounds, runs a 4.6 or 4.5 [in the 40-yard dash], he's just a tremendous athlete with good football intelligence. Has some playmaking abilities, so we want to utilize his athletic ability."
Said Griffen: "For my size, I'm pretty versatile. I can play down; I can play up. They asked me. I'm going to try it out and see how it works out. Whatever they want me to do. It's all about Coach Frazier and the team, making us right and making us better."
Unlike the injured linebacker corps, the Vikings are deep at defensive end.
With Jared Allen and Brian Robison the starters and Stylez White and Adrian Awasom performing well as backups, they are also getting to see more of Christian Ballard's versatility by playing him at defensive tackle and defensive end.
But there is little doubt that the move will be a transition for Griffen.
"You've just got a lot of assignments. You've got to read, read the wide receiver, getting the technique and just knowing your keys, and what to key and what not to key," he said.
"I've just got to study my book. That's what it's all about."
Griffen will be learning the weakside linebacker spot, the one where Erin Henderson is the starter.
PONDER TO START
Rookie quarterback Christian Ponder will start Thursday's preseason finale and play the first half. Joe Webb will play the second half.
"We definitely want to see both guys, Christian along with Joe, create some separation for that No. 2 spot," Frazier said. "Maybe this game will be an indication of which guy should be No. 2."
Frazier said he would probably make a decision after Tuesday's practice on whether or not the others starters will play Thursday, but quarterback Donovan McNabb, who didn't throw a pass during the team portions of Monday's practice, won't play.
BOMAR HEADLINES FIRST RELEASES
The Vikings released 10 players Monday, including quarterback Rhett Bomar, in order to get their roster to the NFL-mandated 80 players by Tuesday's deadline.
The Vikings also waived CB Chris Adingupu, G Conan Amituanai, TE Ed Barham, S Simeon Castille, LB Jonathan Gilmore, WR Andre Holmes, LB Kyle O'Donnell, K Nate Whitaker and DT Colby Whitlock.
In three preseason games, Bomar didn't get to play as the Vikings worked to have their top three quarterbacks familiar with a new offensive system by the start of the regular season. Bomar was arrested during training camp for suspicion of drunken driving, but head coach Leslie Frazier said after the first preseason game that Bomar not playing then was simply a matter of not enough time for all the quarterbacks rather than to discipline Bomar for his arrest.
The Vikings roster has to be down to 53 players by the end of business on Saturday.
Tim Yotter is the publisher of Viking Update. Follow Viking Update on Twitter and discuss this topic on our message boards. To become a subscriber to the Viking Update web site or magazine, click here.