MINNEAPOLIS -- When the Minnesota Vikings began the process of overhauling their offensive line the day after their playoff loss to the Seattle Seahawks by letting go of a coach they'd blocked from interviewing elsewhere only two years earlier, it was clear they wouldn't curtail their efforts to avoid hurting feelings.

Competition was the goal, to a point where even the Vikings' established veterans wouldn't be comfortable. And as the Vikings made a handful of moves on the offensive line leading up to the start of the new league year, they began to lay the groundwork for a training camp where experienced players should have to scrap for starting jobs.

Those efforts led to the return of Phil Loadholt on a restructured deal, a one-year contract for Mike Harris, and a four-year deal for San Francisco 49ers guard Alex Boone. And they don't figure to be done. According to league sources, the Vikings plan to bring former Cincinnati Bengals tackle Andre Smith in for a visit and will continue to monitor the recovery of Chicago Bears tackle Jermon Bushrod from shoulder surgery. If one or both of those players sign with the Vikings, they would join a group that already has seven linemen with at least four years of NFL experience -- not to mention a second-year player in T.J. Clemmings who started every game last year.

Little will be promised on the line, and after two disappointing years for the group, the Vikings have no reason for anyone to be comfortable.

"I’m always going to try to keep shuffling these offensive linemen in," general manager Rick Spielman said last month. "Last year I know Carter Bykowski got hurt with his pec, but we got him off San Francisco’s practice squad. To me, if you can just keep flinging through here -- Mike Harris was a claim guy when he got released from San Diego -- so you've got to constantly turn that position over and constantly keep finding the right combination of guys."

The Vikings are committed to paying left tackle Matt Kalil $11.96 million next season, but the contract structures of the other players on the line allow them to stay flexible. Loadholt, who is returning from a torn left Achilles, has no guaranteed money on his restructured 2016 deal, and only $1.75 million of signing bonus proration left from the deal he signed in 2013. Center John Sullivan, who is returning from back surgery, has no guaranteed cash coming his way in the final two years of his deal. Joe Berger, Loadholt, Kalil and Harris will all be free agents after 2016. The Vikings have few attachments on the line, and their financial structure should inject a dose of urgency into the competition for some players. With new offensive line coach Tony Sparano overseeing it all, the Vikings' linemen will be eager to make a good impression.

That's not a bad thing for a team whose line issues have been the chief impediment on offense. The Vikings believe their offense can be a worthy complement to the league's sixth-ranked scoring defense if they can fix their line, and it didn't sound as though they were done with the process after a few moves at the start of free agency. In the spirit of keeping players on edge, it wouldn't be a surprise if more moves are coming.