Questions remain in Vikings' secondary

MINNEAPOLIS -- On a defense that had plenty of holes last year, it's difficult to argue the Minnesota Vikings' biggest problem was anything other than their secondary. They gave up more points than any team in the league, allowed the second-most passing yards and ranked in the bottom third in the NFL in touchdown-to-interception ratio, first downs per passing attempt and yards per attempt.

The Vikings signed Carolina Panthers cornerback Captain Munnerlyn to play the slot position after their experiment with Josh Robinson backfired last season, and they picked up former Chargers cornerback Derek Cox after San Diego released him in March. With other needs to address in the draft, though, the Vikings didn't add any help for their secondary until the sixth and seventh rounds, when they selected three defensive backs -- Virginia Tech's Antone Exum, Maine's Kendall James and North Carolina's Jabari Price.

Of the three, Exum might have the most immediate chance to contribute. He'll begin his time with the Vikings as a safety, and he's over a year removed from a torn ACL he sustained in a pickup basketball game in January 2013. Exum also missed time with a sprained ankle after his return from knee surgery last season, and he might have slipped in the draft due to concerns about his health and because he had so few chances to prove himself in front of scouts last season. The Vikings will have plenty of competition at safety opposite Harrison Smith, though, and Exum is impressive enough physically that he might attract attention in training camp.

"My strengths are my speed, my size, ball skills, physicality, point of attack and tackling," Exum said in a conference call Saturday. "I feel like I have unique covering ability and also to make the big play at the big moment."

As a whole, though, the Vikings will once again be betting on the ability of young players to develop quickly in the secondary -- and they'll be doing so without the help of another high pick at defensive back. New coach Mike Zimmer initially made his reputation coaching defensive backs, and secondary coach Jerry Gray was previously the Tennessee Titans' defensive coordinator, so the Vikings should be able to give their defensive backs plenty of help. General manager Rick Spielman also left the door open for a later addition in the secondary, adding "you are not done when the draft is done.

"There are going to be some things that happen through the rest of the season, but I know we don't play until September, so there can be a lot of things as we go through," he said.

Short of signing a veteran later in the offseason -- possibly after June 1, when salary cap rules make it easier for teams to shed large contracts -- the Vikings will need defensive backs to emerge quickly. That could be Robinson beating out Cox for playing time now that he's back outside, someone taking charge other safety position or one of the team's late-round picks catching on sooner than expected. Munnerlyn solved a major need in the secondary, but at least at this point, it appears the Vikings will be counting on player development to solve their other ones.