The first wave of NFL free agency revealed at least two indisputable truths:

1. There is no market for veteran running backs.

2. There is wide-spread desperation for credible offensive linemen.

As of Saturday evening, only one notable tailback had agreed to terms on a contract. That was Danny Woodhead, whom the Baltimore Ravens signed to a three-year deal as he continues to recover from a torn ACL. The terms of his deal were largely unknown, but the dollar figure is not expected to be high given his injury rehabilitation. (Fullbacks Mike Tolbert and Kyle Juszczyk also signed deals.)

Otherwise, the NFL has expressed figurative indifference to some players with histories of significant success, including: Adrian Peterson, Jamaal Charles, Eddie Lacy and Latavius Murray. Some are taking visits, but no team felt compelled to make them an offer they couldn't refuse and, with each passing day, the pool of available money shrinks.

Running back Adrian Peterson became an unrestricted free agent on March 9, and he's still exploring his options. Brace Hemmelgarn/USA TODAY Sports

The reasons should be clear. The 2017 draft is stocked with running backs of every desired profile. And a recent ESPN Stats & Informaton analysis of the running back position continues to support the accepted theory that they decline sooner and faster than players at other skill positions.

Tailbacks who have played at least four seasons and received at least 75 attempts in each season peak at age 26 on average. By age 29, their production has dropped by 26 percent, and by 41 percent at age 32. NFL teams pay free agents for projected production, not past achievement. Generally speaking, teams have no incentive to spend real money on running backs when they can draft players who are fresher and more likely to be productive.

On the other hand, the NFL's well-known shortage of offensive linemen led to a blitz on competent players -- especially tackles -- during the initial wave. Seven tackles signed multiyear deals that totaled $304.8 million, while three guards got multiyear deals that added up to $129 million. (Not all of that money was fully guaranteed, but each of the deals contained considerable assurances.)

The Carolina Panthers handed $25.5 million in guarantees to left tackle Matt Kalil, who played in only two games last season because of a hip injury and has been in decline since his rookie year in 2012. The Cleveland Browns were so spooked by the beating their quarterbacks took last year that they signed guard Kevin Zeitler, center J.C. Tretter and also extended promising guard Joel Bitonio.

And the Minnesota Vikings dished out $36.8 million in guarantees to sign tackles Riley Reiff and Mike Remmers, neither of whom was considered the top player available at his position.

The panicked run toward offensive linemen likely reflected a lack of confidence in draft depth. But as the salary cap continues to rise, promising offensive linemen would be well advised to hold off any future decisions until they reach the open market. The NFL figures to have $1 billion in cap space available in each of the next few years, and that money has to be spent somewhere. At the moment, it appears teams want to give it to linemen.

Here's a look back at some of the notable moves from the past few days of the new league year:

Most admirable approach

The New England Patriots are fresh off their Super Bowl LI victory, their second championship in the past three seasons, and yet they are wheeling and dealing as much as any team in the NFL. Their latest move, completed Friday night, was acquiring receiver Brandin Cooks from the New Orleans Saints.

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The Cooks deal was their second trade of the day and capped off what seems like an all-out assault on league competitiveness. This is a franchise determined to crush any tendency toward complacency.

Earlier, they had acquired defensive end Kony Ealy from the Carolina Panthers as part of an exchange of draft picks. Ealy is a classic Patriots acquisition. He has one year remaining on a rookie deal that will pay him $803,660 this season, meaning he'll be in the kind of contract year that often prompts an uptick in production. If nothing else, he is a cost-controlled version of former starter Jabaal Sheard -- who signed a three-year deal with the Indianapolis Colts on Friday that included $12.75 million in guarantees.

When you add Ealy to a haul that includes Cooks, tight end Dwayne Allen (another veteran acquired in an exchange of draft choices) and cornerback Stephon Gilmore, you see a cross-section of the Patriots' perpetually unsatisfied state.

Coach Bill Belichick has no problem swapping out one veteran for another; Allen takes the place of free agent Martellus Bennett. And something tells me Belichick has not a shred of concern for whether incumbent cornerback Malcolm Butler, a restricted free agent who has been offered a $3.91 million tender, is hurt by the decision to pay Gilmore a five-year deal that includes $40 million in guarantees.

Quarterback Tom Brady is the No. 1 on-field reason the Patriots rule the league. And, if they want, the Patriots can still replenish their draft stock by trading backup quarterback Jimmy Garoppolo. But this type of active, use-every-tool approach is a big part of why the Patriots are perennial championship favorites as well.

Most predictable approach -- until it wasn't

The Green Bay Packers, losers in two of the past three NFC Championship Games, appeared to be largely standing pat in the first two days of free agency. As is their typical approach under general manager Ted Thompson, they seemed to be watching the world go by as other teams improved -- in some cases by signing Green Bay's players. (The Buffalo Bills swiped defensive back Micah Hyde, the Panthers grabbed defensive end Julius Peppers, and tight end Jared Cook appeared set on signing elsewhere.)

But as the sun set on Day 2, the Packers emerged with a rarity: They signed the best player available at his position. Bennett, the tight end set free by the Patriots, should be considered a more reliable version of Cook and a weapon who will give quarterback Aaron Rodgers the mid-range option he needs to spread the field.

Martellus Bennett is hoping to make another Super Bowl run with the Packers. Christian Petersen/Getty Images

The Packers have compiled the NFL's second-best regular-season record this decade largely by following the same policy. They use their cap space to sign what they think are their best in-house players -- linebacker Nick Perry was this week's recipient -- and rarely seek proven help like Bennett from outside the program.

This approach leaves the Packers perpetually developing young players who are often promising but not ready to contribute to a championship run. They have made one Super Bowl appearance in Rodgers' tenure. He turned 33 in December. To the admiration of some and the frustration of many, Thompson has seemed uninterested in selling out to pursue a championship to maximize his short-term fortunes with a quarterback who will go down as one of the NFL's best ever.

Bennett isn't a franchise-altering acquisition. But his arrival represents a decision to use more than the usual array of options.

It all brings to mind a saying I heard long ago: If you always do what you've always done, you'll always get what you've always gotten. The Packers want more than what they've gotten, so on Friday at least, they decided to do more than what they usually do.

Most understandable approach

I'm a little surprised at the social media venom directed toward free-agent receiver Terrelle Pryor Sr., who accepted a one-year deal from the Washington Redskins instead of a presumably longer and more lucrative offer from the Cleveland Browns. I don't blame him at all, assuming the Redskins keep quarterback Kirk Cousins on their roster this season.

Put yourself in Pryor's shoes. You produced a 1,007-yard season for a team that had six different quarterbacks take a snap. You're supremely confident in your abilities and believe you've shown only a slice of what you can do.

You could return to the Browns, where your quarterback might be Cody Kessler or perhaps a rookie who will be drafted next month. Or you could sign with the Redskins and catch passes from Cousins, who has thrown for more than 9,000 yards in the past two seasons. You'll have every chance to be the No. 1 receiver there after the departures of DeSean Jackson and Pierre Garcon.

I realize the Redskins once again are a team in turmoil. But other than money, a receiver's No. 1 free-agent criteria is the quality of quarterback. There is almost no way the Browns will have a better quarterback than Cousins in the next few seasons. (Again, that assumes the Redskins don't trade Cousins this spring.) Pryor has a chance for a monster statistical season in 2017, after which he'll be a free agent again and ready to cash in with the highest bidder.

Again, the Redskins are far from a perfect destination. But Pryor bet on himself, and Cousins, and I don't think that's a terrible play. At all.

Most creative move

ESPN's Bill Barnwell took a quick but deep dive into the highly unusual trade that sent Houston Texans quarterback Brock Osweiler and two draft picks to the Cleveland Browns in exchange for a fourth-round draft pick. For the purposes of this post, however, let's acknowledge the big picture: It was a good deal for both teams, even if we don't know the Browns' final outcome yet.

The Texans rid themselves of a player who will go down as one of the biggest mistakes in the history of NFL free agency, all while freeing up salary-cap space and adding to their cash budget. Yes, they had to cough up draft picks to do it, but that is probably a better outcome than keeping him in their locker room.

And the Browns, of course, added another second-round pick to their collection in exchange for the easy absorption of Osweiler's $16 million in cap space. If they are able to trade Osweiler again, they can reduce that hit. But after rolling over $50 million from 2016, and entering free agency with more than $100 million in total space, it won't matter if they have to carry his full number. In essence, it appears the Browns have found a way to use surplus cap space to acquire a draft choice.

Most confusing move

See above. Rarely do we see NFL front offices attempt a move this out of the box. We'll be poring over this one for days and weeks to come.

Best value

I don't have a single objection to the pending marriage between quarterback Mike Glennon and the Chicago Bears. The true commitment is relatively moderate, and the upside for both sides is high.

Ultimately, this deal requires the Bears to pay Glennon like an established NFL starter for one season. He is guaranteed $18.5 million, according to ESPN's Adam Schefter. (At the moment, 12 other NFL quarterbacks have contracts that average at least $19 million annually.)

Mike Glennon, a third-round pick in 2013, goes to the Bears with 18 NFL starts under his belt. Derick E. Hingle/USA TODAY Sports

It's true that Glennon hasn't played (or succeeded) enough to be considered "established," but I can echo what others have said: There are tons of people in league circles who believe he is a starting-caliber talent. The Bears won't be any less competitive with him than they were with Jay Cutler, and at 27, Glennon hasn't hit his ceiling yet. We don't know how good he can be.

If he is as feared, a backup who got overpaid by a desperate team that tried to get cute, then it was a one-year mistake for a franchise that has plenty of work to do in other areas. There is nothing about this signing that precludes the Bears from drafting a longer-term answer. They entered free agency among the NFL leaders in salary-cap room, and who other than the McCaskey family cares if they spent their cash wisely?

As for Glennon, there weren't many teams who were willing to hand him the keys even for one season. He'll get a legitimate chance to show he can be an NFL starter, and the Bears will get a relatively expensive one-year rental that could grow into something more.

Jaguars gonna Jaguar

As we noted earlier this week, the Jacksonville Jaguars wrote 28 contracts worth an NFL-high $488 million during the past three free-agent markets. With only 11 wins to show for it, and having already jettisoned a majority of the players they signed over that period, they were the classic example of a team focused more on paper improvement than actual team-building.

But even with a new football czar (Tom Coughlin) and coach (Doug Marrone), the Jaguars were back to their old tricks Thursday. They guaranteed defensive end Calais Campbell, who turns 31 in September, $30 million and then won the bidding war for cornerback A.J. Bouye with a bid of $26 million fully guaranteed.

Some of Campbell's money might be guaranteed for injury only, and there is no doubt that in a vacuum, both he and Bouye are nice players. But history tells us this is no way to build a contender. There are reasons why the Arizona Cardinals didn't bring Campbell back, and why the Texans didn't hold on to Bouye. Those reasons will be evident in the coming year(s). Wake me up when the Jaguars start spending big money on retaining their own draft choices and not on someone else's discards.

Favorite signing

Defensive back Micah Hyde caught my eye during a Green Bay Packers minicamp in 2013, and to me, he has been one of the NFL's most valuable and versatile players since then. Hyde said in a statement that the Packers never made him an offer, a surprising revelation for a team that almost always locks up its best players, but their loss is the Buffalo Bills' gain.

As a part-time player for the Packers, Hyde had eight interceptions, four sacks, six fumble recoveries and three punt returns for touchdowns. He can play cornerback or safety, functions well in blitz packages and has a clear nose for the ball. The Bills will expect him to be a full-time player, based on a five-year contract that includes $14 million in guarantees, but there is every reason to think Hyde can handle it.

I usually hate when coaches describe someone as "just a good football player," but that really is what Hyde is. He is the kind of "glue player" that every team needs. I can't argue with the Packers' decision to prioritize a pass-rusher (linebacker Nick Perry) over a defensive back, but Hyde leaves a multifaceted role that will be difficult for one player to fill.

Funniest assertion

The San Francisco 49ers' decision to sign quarterback Brian Hoyer should not, under any circumstances, be viewed an obstacle to pursuing Washington Redskins quarterback Kirk Cousins.

Cousins is caught in the Redskins' current drama and already has asked owner Dan Snyder to trade him. Niners coach Kyle Shanahan would love to have him. Hoyer? He's the guy you don't want starting more than a handful of games. History tells us that he either runs out of gas, or defenses catch up to him, or both, over the course of a season.

In his career, according to ESPN Stats & Information, Hoyer has a 60.4 Total QBR in the first two months of a season. In the final two months, his QBR is 37.3. He is a high-end backup quarterback, which means he can handle himself respectably in limited playing time. No one in the NFL thinks the 49ers are content to enter the season with him as their unquestioned starter.