One man's garbage is another man's gold.

Speaking of NFL free agency …

The Vikings got better this week. Whether they get good again may depend on whether they strike gold with what Detroit considered garbage.

Riley Reiff became the Vikings' prized offseason acquisition and starting left tackle as soon as the free-agency signing period opened Thursday. It must have been a welcoming moment for a former first-round draft pick who spent the past year feeling more and more unwelcome in the Motor City.

Reiff was selected 23rd overall in 2012. From that season until draft day a year ago, he was Detroit's left tackle.

The Lions didn't consider him up to the task. So they drafted Ohio State's Taylor Decker 16th overall last year and made him their starting left tackle immediately. Reiff was moved to right tackle and allowed to play out the final year of his contract at age 27.

The Lions beat the Vikings twice but went 7-7 otherwise. Again, Detroit targeted its offensive line for an upgrade. Again, Reiff didn't make the grade.

He officially was wheeled to the curb this week as Detroit made former Raven Rick Wagner the league's highest-paid right tackle at more than $9 million a season.

The Vikings, meanwhile, paid Reiff like a starting left tackle, guaranteeing $26.5 million of his five-year, $58.75 million deal. A day later, they essentially confirmed Reiff as their left tackle when they signed Carolina's Mike Remmers, whose only time as an NFL left tackle came as an emergency replacement for the injured Michael Oher last year.

The general mood of the more vocal Vikings fans starving for an NFL-caliber offensive line appears to be, "That's … it? That's all you got?"

Many have expressed concern that Reiff's skills are more suited to playing right tackle. And, of course, the modern fan also is quick to reference Pro Football Focus. As in, "Do you know Reiff and Remmers were ranked 48th and 51st, respectively, last year!" or "Dontcha know PFF has never, ever ranked Reiff in its top 25!?"

People want to know why Matt Kalil went to Carolina, or why Andrew Whitworth went to the Rams for less money, or why Wagner didn't come here. We'll never know the pecking order on General Manager Rick Spielman's wish list, but also keep in mind that free agency is a two-way street.

This isn't a board game. These are human beings with freedom to choose. Sometimes, a guy wants to go to Carolina to play with his brother while getting $25 million guaranteed. Or sometimes a guy picks LA, LA Land over the Land of 10,000 Frozen Lakes.

Adding two tackles with middle-of-the-road reputations isn't a "wow" week. But the Vikings did get better by adding two durable, starting-caliber tackles under the age of 29.

They also lost six of their own free agents: Captain Munnerlyn, Rhett Ellison, Jeff Locke, Audie Cole, Charles Johnson and Kalil.

They've replaced Kalil. They drafted Mackensie Alexander in last year's second round to replace Munnerlyn, so try to trust the youthful replenishing process and DB Whisperer Mike Zimmer on that one.

They also drafted David Morgan in last year's sixth round to replace Ellison. They didn't want Johnson. And Locke and Cole can be easily replaced.

The Vikings went into free agency at a little more than $38 million below the $167 million salary cap. According to overthecap.com, they're now $26.96 million under the cap, which should leave them enough room to fill other roster holes heading into the draft.

The Vikings, however, would be wise to maintain offensive line as a priority. Yes, they got better up front this week. But, as we all know, that's not saying much.

Better might never be good enough until this team can consistently draft and groom reliable long-term starting linemen.