Ryan Grigson

Every successful NFL team can trace its good fortunes to the draft. Yes, free agency plays an important role, and not everyone eschews the open market like the Green Bay Packers. But you can't build a strong 53-man roster with free-agent signings, no matter how cost-effective those deals might be.

Winning teams thrive because they've found assets in the NFL Draft. And a lot of times, the opposite is true for bad teams: Years of poor drafts have depleted their rosters and dug them into a deep hole. Perhaps more than free agency, the draft is where general managers extend or shorten their tenures with teams. You only get to throw away so many first-round picks before management decides to bring in a fresh face.

So while nobody's getting fired before the 2016 season gets underway, it's fair to say some GM fates will be sealed at this year's NFL Draft. In no particular order, here are the six general managers facing do-or-die situations this year.

Les Snead, Los Angeles Rams

Les Snead

That's what happens when you sell out for the first overall pick: You face incredible pressure to draft a winner. And let's give Snead credit where credit is due: In April 2012, he wisely traded the rights to Robert Griffin III for a total of eight draft picks that yielded several entrenched starters for the team.

And L.A. still has some great young players on its roster, for which you can thank Snead. But he overpaid Tennessee immensely for the No. 1 pick in this year's draft, and the only way to justify that move is to draft a future franchise quarterback. Whether it's Carson Wentz or Jared Goff, Snead's entire draft grade will depend on how that first pick turns out -- and if it bombs, Snead may be headed out the door.

Jerry Reese, New York Giants

Jerry Reese

Reese has GMed the Giants to two Super Bowls, but what has he done for the Giants lately? Outside of drafting OBJ and throwing Tom Coughlin under the bus this winter, not much. The Giants became a middling team for a few reasons. One of them was injuries, which isn't Reese's fault. But poor draft picks and questionable free-agent signings are squarely on his shoulders.

His decision to spend nearly $200 million this offseason -- in some cases overpaying on free agents -- looks like a short-term fix to a long-term problem. If Reese can't replenish the well with some promising draft talent, he'll find himself in a hole too deep to spend his way out of.

Trent Baalke, San Francisco 49ers

Trent Baalke

Baalke has survived a lot of upheaval with San Francisco, and the successes of the Jim Harbaugh days were built largely on talent that the 49ers either drafted or molded into big-time contributors. But Harbaugh is gone, as are a number of key players. San Francisco is on its third head coach in as many years, the roster remains depleted and the team has over-invested in a quarterback it doesn't love.

San Francisco can always unload Colin Kaepernick, but without a better option it remains a moot point. Baalke needs to prove he can rebuild through the draft. Otherwise, the 49ers will continue to struggle, and the only constant will be Baalke himself.

Ryan Grigson, Indianapolis Colts

Ryan Grigson

The Colts have been successful under Grigson, but that success is a bit of a mirage: The team benefited from a laughable division and the leadership of Andrew Luck. But drafting Luck with the No. 1 pick wasn't exactly equivalent to proving the existence of gravitational waves.

Outside of its franchise quarterback, Indianapolis has been starved for young talent, and Grigson has done a poor job acquiring assets through the draft. This is, after all, the man who traded a first-round pick for Trent Richardson. That alone brings your qualifications under fire. If he doesn't reload the roster through this year's draft, he needs to go.

Doug Whaley, Buffalo Bills

Doug Whaley

Whaley has made Buffalo respectable, but he's also led the franchise to the edge of purgatory. The team has a good-but-not-great quarterback in Tyrod Taylor, a decent-but-overpaid running back in LeSean McCoy, and an emerging star receiver in Sammy Watskins who still hasn't justified his price (the team traded two first-round picks him).

There's also the problem of location: NFL players aren't fighting one another to play in a location like Buffalo. If Rex Ryan's team is going to be a playoff contender, it needs an injection of talent and playmaking. Whaley's best bet is finding those answers in the draft.

It's hard to say whether Whaley will be able to get that done. But if he can't, the Bills are at risk of hitting a wall before even reaching the postseason. It's far from certain that the team would axe Whaley after one bad draft, but it might be the tough decision Buffalo needs to keep moving forward.

Mickey Loomis, Saints

Mickey Loomis

Loomis has a situation similar to Reese's: He has accomplished some things, but not lately. Since winning Super Bowl XLIV , New Orleans seems to get a step worse every year, winning just one NFC South division title since 2009.

Talent is slowly trickling out, and the Saint have very little to show from the past few drafts. That's got to change quickly: At 37, Drew Brees is on the decline, but he can still lead a playoff contender if he's got the right supporting cast. New Orleans has enjoyed a lot of continuity over the past decade, but the team should have Loomis on notice entering the draft.

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