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Good news, combine fans! The NFL Scouting Combine may have wrapped up three weeks ago, but the NFL loves watching huge men run 40-yard dashes in compression shorts even more than you do! The all-new veteran combine takes place March 22 at the Arizona Cardinals' training facility in Tempe, Arizona. A total of 107 NFL hopefuls, from semi-famous ex-players to obscure practice-squad hangers-on, will spend Sunday running dashes and performing drills in a stripped-down version of February's rookies-only event. Their goal: reignite their NFL careers.

How did this veteran combine spring to life? What's the point? Who's participating? Who decided who gets to participate? Where's Tim Tebow? To answer these questions, I spoke to Matt Birk, the former Vikings and Ravens center who is now the NFL director of football development, as well as some other experts and participants.

Here's everything you wanted to know about the veteran combine but didn't know who to ask.

An "NFL Veteran Combine"? Whose zany scheme is this?

The NFL has in-house exploratory committees that investigate all manner of ideas and ventures. Birk took over as director of football development seven months ago, but the league has been tinkering with the veteran combine concept for at least a year and a half.

What's the point? More hype? More NFL Network programming?

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If the NFL was just looking for more hype and programming, it would probably come up with something buzzier than tune in to watch Mike Kafka throw footballs on the Cardinals' practice field!

"In football development, there are two boxes that we try to check off," Birk said. "One: Is it good for the players? And two: Does it provide a service to our clubs? Does it make our clubs' lives better?

"We think [the veteran combine] streamlines a process that, in the past, was a little bit arduous and not very efficient."

What arduous past process is Birk referring to?

The weekly workout process for street free agents.

General managers have walked me through this process several times over the years. Most teams schedule workouts for players who are not under contract, every Tuesday during the regular season. Usually, each team focuses on a specific position group per week: linebackers this week, receivers next week. A sudden injury rash could change the priorities. Teams also conduct workouts like these intermittently in the offseason.

Assistant coaches conduct the workouts; folks from the general manager's office or pro scouts are usually in attendance. Sometimes, the best player at the workout gets signed to the practice squad or to fill an injury need. More often, the team takes note of the players who look best and keeps their contact info filed away for when it's needed.

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There are all sorts of scheduling and timing headaches for both players and teams during the tryout process. The player may have to decide among five or six teams offering tryouts at his position on any given Tuesday. Teams don't always get the best snapshot of the available "street" talent.

In the offseason, free agency and the draft create moving targets that make it hard for teams to carve out the resources to really focus on the available talent that lies just off the radar. "It is a little bit 'out of sight, out of mind' right now," Birk said.

The playing field isn't level for finding talent this way, either; an established general manager who values this process (Packers fans can nod here) is going to get much more from weekly tryouts than a novice with an inexperienced staff.

Do teams really think these "off-the-street" players are worth a look?

Absolutely. I spoke to former Broncos general manager Ted Sundquist about the veteran combine recently. "I love this pool of talent," he said. "It doesn't cost you very much as a club. It costs hardly any signing bonus."

Sundquist went on to point out that most players are young enough that their college scouting reports are still accurate, and most have enough camp or practice-squad experience to prove they can handle the NFL rigors. "They hit the ground running."

So who will attend this veteran combine?

According to Matt Birk, "These guys are the Ph.D.s: the poor, hungry and determined."

Cute. Can you be more specific?

Most of the names would not mean much to most fans. Here is a partial All-Star team of some of the best-known players. I skipped the offensive line and some other positions because, as you will guess from the names at the high-profile positions, things get really obscure in the trenches.

Quarterback: Tyler Wilson. Former Arkansas star. Had brief stints with the Raiders, Titans and Bengals in 2013 and 2014.

Quarterback: Mike Kafka. Former Eagles backup who had cups of coffee for the Jaguars, Patriots and Buccaneers, plus workouts for many other teams. Kafka has been a popular "emergency quarterback for hire" for years who gets a little extra attention because his name inspires bloggers to use the same Metamorphosis joke over and over again. It really bugs me.

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Running Back: Michael Bush. Rushed for 3,250 yards as a spot starter for the Raiders and Matt Forte's backup in Chicago. Last seen on the Cardinals payroll last season, during their running back injury/suspension/retirement rash.

Running Back: Mikel LeShoure. Former second-round pick; led the Lions in rushing in 2012. Has had an Achilles injury, battled weight problems and done all the little things that get a talented rusher shunted to the back of the bench. Spent 2014 working out for Colts, Broncos and other needy teams but never signed a contract.

Running Back: Felix Jones. The 22nd player taken in the 2008 draft and a very productive committee back for the Cowboys for several years. Jones moved from the Cowboys to the Eagles to the Steelers in 2013, got stashed behind the Van Gogh in Mike Tomlin's doghouse (the dreaded zero-tolerance fumble policy) and spent 2014 attending the occasional workout.

Wide Receiver: Lestar Jean. Le star of several Texans preseasons—he caught three exhibition touchdowns in 2013—Jean caught 46- and 54-yard passes for the Texans' 2012 playoff team in the regular season but had his career derailed by nagging injuries and inconsistency. Signed with the Vikings last year but was waived with an injury settlement.

Wide Receiver: LaQuan Williams. Hung around the bottom of the Ravens depth chart for years because of his special teams chops.

Tight End: Matt Veldman. Toolsy 6'7" guy from North Dakota State who has had stints on the Jaguars, Buccaneers, Lions and Redskins.

Defensive End: Michael Sam. Former Mizzou star. Spent last preseason with the Rams and was on the Cowboys practice squad for a few weeks. Openly gay.

Defensive End: Adam Carriker. Thirteenth player taken in the 2007 draft. Started for four years for the Rams and Redskins before a major 2012 knee injury that required multiple surgeries. Carriker posted a video last summer dead-lifting over 500 pounds to show that he is ready for a return.

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Defensive End: Jamaal Anderson. The eighth player taken in the 2007 draft. Started 48 NFL games. Has not played a snap since 2012. Carriker and Anderson stand out a bit on the veteran combine list; running back is the only other position with a handful of players who could once have been considered NFL regulars.

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Linebacker: Thomas Keiser. Played for the Panthers, Chargers and Cardinals. Intercepted Peyton Manning in the fourth quarter of a game in Week 15 to seal a Chargers win, giving him a flicker of fame. Currently on the San Jose SaberCats' Arena Football League roster.

Linebacker: Brian Rolle. Antrel Rolle's cousin. Former Ohio State star. Started for the 2011 Eagles.

Cornerback: Johnny Patrick. Played nickel for the Saints and Chargers from 2011-13; like Keiser, he made a few big plays for the 2013 Chargers. Spent the 2014 preseason with the Jets but was released last August.

Safety/Return Man: Akwasi Owusu-Ansah. Selected by the Cowboys in the fourth round of the 2010 draft, ahead of Kam Chancellor. (Sorry, that's mean.) Returned kicks and punts for the Cowboys between injuries for two seasons. Bounced around the Jaguars, Raiders, Lions and Saints practice squads until last spring as an all-purpose athlete who occasionally bubbled up to an active roster.

That's quite an All-Star Team. If you'll excuse me, I want to see what's on Netflix.

The real action for NFL personnel departments probably doesn't involve quasi-celebrities like Felix Jones or Carriker. Teams will want their scouts to sift through the dozens of guys I didn't name.

The invitation list is full of 24- to 25-year-olds who spent a few weeks in one team's camp or signed a futures contract with another. In basketball, these guys would be in the D-League. In baseball, they would be in Triple-A. In the NFL, they scatter to the hinterlands: the CFL, Arena Football, those wacky I Can't Believe It's a Football League! leagues that come and go before anyone notices, or just some performance facility to work out and wait for phone calls.

How did players apply to the veteran combine?

There was an online application. It has been taken down now, but it was pretty minimalist: basic contact information, height and weight, some questions about when and where the applicant last played football.

Anyone who was not eligible for the "real" scouting combine (this year's or any future year's) and was not under contract to an NFL team could theoretically have applied, including you, me, Usain Bolt and Terrell Owens. Birk said that there were about 2,000 initial applicants. Pre-screening eliminated any high school heroes who led West Catholic to state championship glory in 2003 and have been playing Madden ever since.

That's a shame. Vince Papale from the movie Invincible would not have been eligible.

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In fact, Vince Papale from real life would have been eligible: The real Papale (who made the Eagles after an open tryout and became a Philly folk hero in the late 1970s, then became the subject of a 2006 movie) had played in the World Football League and was a college track star. Some of the players on the invitation list have that kind of resume: They went to tiny schools and/or played in defunct leagues. But no, the mook from the movie who tended bar and played in the parking lot would not make it through the initial whittling of 2,000 applicants to 107.

The pruned list was then handed over to a panel of NFL personnel evaluators. They ranked the remaining applicants in terms of their worthiness to participate. The final invitation list is the result of those rankings.

What criteria did that panel use?

Birk said the committee looked for players who would most benefit from the experience: guys who recently left the NFL, perhaps due to an injury, perhaps because they just slipped off the back of a roster and through the cracks. "Most of them are unknown commodities," Birk said. "Their resumes aren't very long. Maybe clubs haven't had a chance to have a look at them."

Why aren't Tim Tebow and Vince Young on the list?

The NFL will not comment on why individual players will not attend.

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Using Birk's criteria for selection, it is easy to understand why someone like Young was not selected. The veteran combine is for guys who don't have any tape. Young has 50 NFL starts. The veteran combine is for players stuck on the weekly tryout treadmill. Young signed well-publicized one-year contracts each of the last three offseasons, though his stints grew so short (11 days in May with the 2014 Browns, for example) that the contracts could have just been carried by conveyor belt from printer to Young to shredder. NFL general managers believe they have ample documentation of Vince Young's viability at this point.

One agent told me that he wouldn't recommend the veteran combine to any client who still had a reasonable chance of getting a one-on-one workout invitation from teams. The list suggests that not every player or agent felt that way, but some parties may be withholding judgment on the value of this event until it establishes itself.

Tebow probably belongs in another category. Tebow always belongs in another category. The Eagles just gave Tebow a workout, and it's unlikely that other teams have forgotten about his existence or misplaced his contact info, which is the kind of thing that could happen to Ben Gottschalk.

What about Michael Sam? Doesn't he belong in his own category?

Take away Sam's sociopolitical fame, and he fits squarely among the dozens of no-names on the invitation list. He was a late-round pick who bounced between a pair of teams and is currently a street free agent.

There are good reasons for teams to want a second look at Sam in drills; he trained for last year's combine under the pressure of having just publicly come out of the closet, which is the kind of out-of-box situation that could easily have added a few hundredths of a second to his times.

Won't Dancing with the Stars interfere with Sam's performance at the veteran combine? Or vice versa?

Lynn Swann used ballet to stay in shape and cross-train for flexibility and balance. Lots of guys do yoga and other flexibility-based exercises. Preparing for the NFL is not all about doing squats and eating buckets of broken glass. Also, last I checked, three former NFL players have won Dancing with the Stars without shattering our national perception of masculinity.

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But yes, I hear you: participant on a dance show, not the traditional "hungry NFL wannabe" image for a guy trying to prove that he is about football, not fame. Most of the other veteran combine attendees are doing whatever side jobs bring in the most money right now; like Sam, few of them made any real NFL money.

Sam's "side job" is as a cultural figure, and that may give someone who is seeking reasons to say no an easy reason to say no. If he takes the field in front of stopwatches and cameras and outperforms 22 other defensive ends and linebackers, it shouldn't matter who he is dancing with.

I think the NFL just invited Sam because it doesn't want to appear homophobic.

Yeah, the NFL has been really savvy about keeping up appearances lately, hasn't it? If Sam runs a 4.5 40-yard dash and doesn't get any offers, that clever plan will backfire. Let's wait for the results before we amend any and all conspiracy theories.

Aside from Sam and some broken-down running backs and defensive ends, this event just sounds like a bunch of faceless guys who flunked multiple tryouts running on a track.

You should probably think of it as a bunch of faceless guys who passed multiple tryouts running on a track. To get on multiple rosters/practice squads over the course of two or more seasons, these players often had to fly to open tryouts and outperform a bunch of guys at their own position.

"These guys have had the door slammed in the face," Birk said. "They've been told to 'bring your playbook, go see the head coach.' They've been through that once, twice, three times. And these guys are still pursuing their dream.

"When it comes to this list, what you see is that if a guy shows up to this event, and he is in shape, works out hard, you'll know that he's got the drive. That's the first prerequisite you need to play football."

Also, not all of these guys are "faceless" if you jog your memory a bit. Some were well-known college players like Jerrod Johnson.

I remember Jerrod Johnson. He started at Texas A&M a few years ago. He's the reason Ryan Tannehill switched to wide receiver for a year: Johnson won the quarterback job.

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Johnson was (and is) 6'5", threw for 3,579 yards and 30 touchdowns for the Aggies in 2009, and also rushed for 506 yards and eight touchdowns that year. He played for Mike Sherman, the former Packers coach who coordinated the Dolphins offense for a few years, so he had pro-caliber training. But he wasn't even drafted.

Why not?

Johnson suffered a rotator cuff injury midway through his senior year. He tried to participate in the Shrine Game in 2011, but he was not healthy, and he looked terrible. He threw at the combine, but he was not healthy, and he looked terrible.

"I embarrassed myself at the combine," Johnson told me last week. "I thought I was healthy, but I wasn't. Then I went to the Eagles and embarrassed myself again."

The Eagles brought Johnson to training camp in 2011, but Johnson recalls that his throwing motion was ruined after months of trying to play through the injury. He had a hard time even throwing 15- to 20-yard passes. Head coach Andy Reid eventually realized Johnson was not healthy and sent him home. By then, the pain was long gone, but his delivery was so "jacked up" that he was a shadow of the quarterback who starred at Texas A&M. "It was eight months of re-learning to throw a football from scratch, like a third-grader."

Johnson spent the 2012 preseason with the Steelers. The Seahawks signed him after the 2013 draft, then released him when veteran backup Tarvaris Jackson became available. The Bears kept him on the practice squad for much of the 2013 season. In between, Johnson had two stints in the doomed UFL; one team went out of business before he could take a snap.

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When the Bears drafted David Fales and added Jordan Palmer and Jimmy Clausen to the roster in 2014, it was clear that Johnson would be the fifth quarterback, at best, on the offseason roster. Head coach Marc Trestman recommended Johnson to the Montreal Alouettes. Johnson headed north, but he arrived late for the start of the CFL season and got stuck behind former Tennessee star Jonathan Crompton and former 49ers starter Troy Smith on the depth chart.

So Johnson has been good enough to impress some tough-cookie evaluators, but nothing he does ever results in snaps. This is Johnson's chance for a combine do-over. "There are 28 teams who have never seen me throw or have ever been around me. One of those teams will see me again and decide I am worth taking a shot on."

The veteran combine list is full of stories like that.

What will Johnson and the other "Ph.D.s" do at the veteran combine?

Combine stuff: 40-yard dashes, three-cone drills, some position-specific drills. Birk calls it a "basic threshold workout."

Will they undergo physicals?

No.

Will they engage in panel interviews like the ones at the scouting combine?

No.

I thought the physicals and panel interviews were the most important events at the scouting combine from a team perspective.

The 300-plus players at the regular scouting combine are just 10-12 weeks removed from regular on-field action. Their scouting evaluations are farmers' market fresh. Teams enter the scouting combine seeking knowledge about unknown medical conditions and a better understanding of a player's personality, character and intelligence.

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The 107 players at the veteran combine have no recent game footage. Some could have spent the last 18 months diving into the chocolate fountain at Golden Corral or chopping down trees in the Siberian mountains. Teams need to see them run, cut and throw.

"This is an event where a guy can catch a team's eye," Birk explained, noting that evaluators may have some opportunities to informally talk with players during the event. "What we foresee is teams bringing these guys in afterward to dig a little deeper."

Players will run and jump Sunday to earn future interviews and physicals.

Why March 22? Why Tempe?

The NFL holds its owners' meetings in Phoenix on the weekend of March 21-23, so high-level executives are already scheduled to be in the area. The league also hosts its "super regional combine" in Tempe on Saturday, March 21, so a lot of scouting and personnel people will also be in town. The veteran combine saves everyone from having to make a separate trip, particularly scouts who are rushing from college pro day to college pro day this time of year.

Wait…the super regional combine?

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Yep. In addition to the scouting combine in Indianapolis that we all know and love, the NFL hosts regional skill-position combines throughout February and early March. These events feature lots of small-school and Division II or III guys, plus folks from semipro leagues or others with a $150 application fee and enough athletic credibility to pass a sniff test of a screening. ("NFL Regional Combines are not fantasy camps," warns the official website.)

Once the lower-level scouts assigned to these events rummage through the football equivalent of an old barn full of rusty motorcycle parts, the top performers earn invitations to the super regional combine.

So the "best of the rest" of the 2015 draft class will be in Tempe on Saturday, then the second-chance veterans will be there Sunday. And the big bosses are in the region for meetings, anyway. It's enough of a conveniently packaged bundle of cheap talent to get general managers and scouting directors to take the event seriously. The applicants also get assurance that the event is worth their while: They are not flying to Tempe to perform in front of three junior scouts with an egg timer.

Why are 107 players participating?

Birk and the organizers used 100 participants as a ballpark figure for how many players they could give a fair, thorough and productive workout in one day. They went a little over.

So this is a low-key, one-day, 107-player event this year. When does it turn into a seven-day media marathon that consumes our lives, with Mike Mayock rapping and Rich Eisen running sprints? Next year?

Birk joked that "the possibilities are endless." But he also noted that both he and the NFL want to make the veteran combine a viable, logistically sound event before anyone gets any ideas about expansion.

A few people in the know have told me that the NFL has not abandoned the idea of a developmental league. There are several sticking points, only one of which is money. The NFL won't be placing minor league teams in Barcelona or Germany if it ever happens.

Another major roadblock keeping the NFL out of the minor league business is the simple fact that most evaluators don't see a lot of value in scouting a bunch of minor league games. The Shrine Game and Senior Bowl are fine examples: Scouts skulk around the events all week, watching every single drill, then fly out of town before the actual game!

No one really wants to watch batting practice in baseball: 100 games of Double-A ball tell an incredibly complete story of a player's potential while giving him the experience he needs to get better. Basketball is the same way: A bunch of Sioux Falls vs. Erie games can provide both scouting knowledge and player development, but no one really needs to see shootarounds.

But in football, isolated one-on-one drills (receiver versus cornerback, guard versus defensive tackle) and variations of two-on-two or seven-on-seven provide the bulk of both the evaluative and player development nutrition.

I don't think the veteran combine will lead to a D-league. I do see it expanding in the future, perhaps to two or three days or to a regional/super regional format like the one used for rookies. When you look at the layers of competition and control that other major sports leagues have in place, it's shocking that the next step down from the NFL is the CFL, arena ball, some fly-by-night league that plays at a high school, or working at Foot Locker.

If nothing else, the veteran combine creates the opportunity to get validated as a "short list" near-NFL player for guys who do not manage to get an actual contract. Two or three events like this—one in the first week of June, perhaps, and another in Mobile during the week of the Senior Bowl—would create a substantial group of "Triple-A" NFL players.

What about the players who perform at the veteran combine, fail to stand out and fail to get even an NFL nibble?

That may be the signal some players need to move on with their careers in Canada or the regular workforce.

"That's not the desired outcome for any of our participants," Birk said. "But it can provide that closure, which can be a valuable resource."

Mike Tanier covers the NFL for Bleacher Report.