Vikings clearly relying on coaching to improve offensive line

Less than a week into free agency, the Vikings' philosophy for 2019 has taken shape. Namely: They're going to go with (and pay) the guys with whom they've had success in the past.

That means, at least at this point, giving defensive-minded head coach Mike Zimmer as many familiar defensive resources as the salary-cap challenged franchise can afford. Re-signing linebacker Anthony Barr and restructuring Everson Griffen's deal were the biggest moves in that regard.

It also means any attempted upgrades to the offense — specifically the offensive line — figure to be far from splashy. The Vikings find themselves with plenty of offensive line needs but limited cap space in an offseason when a lot of…