A breakdown of the first week of free agency for the Minnesota Vikings:

Most significant signing: The Vikings made a point to address their offensive line after two disappointing seasons, and they kicked off free agency by landing 49ers guard Alex Boone on a four-year, $26.8 million deal. Boone should provide a much-needed dose of grit for the Vikings' offensive line, where he figures to line up next to Matt Kalil on the left side, and his addition reflects the Vikings' overall push to get tougher along their offensive front.

Alex Boone should provide a much-needed dose of grit for the Vikings' offensive line. AP Photo/Rick Scuteri

Most significant loss: Cornerback Josh Robinson is the only free agent the Vikings have lost, and it was clear at the Senior Bowl in January the team planned to move on from Robinson after four enigmatic seasons. The team released wide receiver Mike Wallace before the start of the league year. The Vikings could need an addition to their receiver group after Wallace signed a two-year deal with the Baltimore Ravens, but had the Vikings deemed it essential to keep Wallace, they wouldn't have let him go.

Player they should have signed or still could sign: The Vikings hosted former Bengals tackle Andre Smith on a free agent visit Sunday and Monday and could still add him to their group as they look for further competition along the line. Smith, who spent five seasons with Vikings coach Mike Zimmer in Cincinnati, would figure to be the favorite to start at right tackle should he sign with the Vikings.

What’s next: The Vikings have several in-house free agents they could still look to re-sign -- linebacker Chad Greenway chief among them -- and if they don't sign Smith, they could continue to explore their options on the offensive line.

Overall grade: B-plus. The Vikings were never going to be the most active team in free agency, and it remains to be seen if they've done enough to improve the safety position next to Harrison Smith, but they've made smart moves to improve the offensive line and add depth on defense, while taking care of their internal free agents.