Joel A. Erickson: As NFL free agency opens, franchises and fans know to be wary — but sometimes that perfect fit is out there _lowres

New Orleans Saints quarterback Drew Brees (9) points toward his helmet during the first half of an NFL football game against the Washington Redskins in Landover, Md., Sunday, Nov. 15, 2015. (AP Photo/Mark Tenally)

Free agency has become so much of a cautionary tale in the NFL that it’s almost cliché.

Buyer beware, the experts say annually as free agency opens. The proof is everywhere, every time teams cut loose yesterday’s splash signings, reduced now to front-office regrets more valuable for the cap space that can be gained by putting them back on the open market.

The New Orleans Saints have been down that road. When the new league year opens at 3 p.m. Wednesday, the Saints are expected to cut ties with last spring’s free-agent darling, cornerback Brandon Browner, after just one season, the ultimate admission of a past free-agent mistake. A pair of New Orleans’ other big splashes from 2014 and 2015 free agency, safety Jairus Byrd and running back C.J. Spiller, haven’t produced juice that’s worth the squeeze so far because of injury. For all of those reasons, a lot of Saints fans find themselves approaching this free agency period with one eye closed.

But the Saints are far from alone. Ask the Philadelphia Eagles, who spent the legal tampering period trading away Byron Maxwell and DeMarco Murray, their two biggest prizes in a wild offseason splurge last March. Or the Miami Dolphins, who watched their $60 million investment in 2013, Mike Wallace, cut by Minnesota just one year after the Dolphins unloaded him on the Vikings. Miami responded to that mistake by signing one of the NFL’s biggest defensive stars, Ndamukong Suh, to a record deal last year to put them over the top.

Instead, the Dolphins stumbled out of the gate, fired their coach and find themselves spending on another defensive line star, Mario Williams, once again.

Cautionary tales like the Eagles, Vikings and Dolphins are scattered all over the NFL. Ever since the new CBA limited the financial impact of poor draft picks, free agency has replaced the draft as the NFL’s biggest crapshoot, a place a team can get burned far more easily than it can get better.

For all those reasons, and there are plenty, the smart money in the NFL is on the draft-and-develop approach. At least one franchise, the Green Bay Packers, has built a perennial winner by annually ignoring free agency, preferring instead to fill its holes with as many draft picks as possible. With examples like the Packers and Pittsburgh Steelers to cite, NFL experts often thumb their nose at free agency’s big spenders now, the news of each big contract met with some skepticism.

So why, with all of that heartbreak, will NFL teams still be trying to fight furiously for the right free agent once the new league year begins Wednesday afternoon?

Because free agency still can put a team over the top. Ask the Denver Broncos, who spent big on linebacker DeMarcus Ware, cornerback Aqib Talib, safety T.J. Ward and wide receiver Emmanuel Sanders two years ago — not to mention a quarterback named Manning four years ago — and watched their haul help lead them to the Super Bowl. Or the New England Patriots, who rented cornerbacks Darrelle Revis and the aforementioned Browner for a year and rounded out a defense capable of helping Tom Brady back to the top. Or the Seattle Seahawks, who matched their draft-and-develop secondary with free-agency splashes on the defensive line in Michael Bennett, Chris Clemons and Cliff Avril to win the Super Bowl in 2013.

And it’s not just the Super Bowl teams that find ways to plug holes in free agency. Oakland, flush with unreasonable amounts of cap space the past two seasons, got contributions from wide receiver Michael Crabtree, center Rodney Hudson and defensive tackle Dan Williams to return to respectability this season. The New York Jets missed on veteran cornerback Antonio Cromartie, who already has been let go, but they also brought in Revis, nickelback Buster Skrine and free safety Marcus Gilchrist last year to give Todd Bowles enough talent to get to 10 wins in his first year as coach. Players with injury histories, like Darren McFadden and DeAngelo Williams, made big impacts for the Cowboys and Steelers.

Even the Packers, for all their aversion to free agency, owe a great deal to Charles Woodson, Julius Peppers and Ryan Pickett, three veterans culled from the free-agent ranks.

The Saints already knew this. The best player in franchise history, Drew Brees, was a free agent, but he has been surrounded by players like Scott Fujita, Darren Sproles, Jabari Greer and Keenan Lewis over the years.

For all of its foibles, free agency can still work, provided that a team drafts well enough to provide the foundation, a point that has been a problem for the Saints in recent years. Find the right fit, though, and the right free agents can help a team take the next step.

Figuring out who is going to be that fit, now that’s the tricky part.