Last season, Cedric Griffin tore his ACL in the NFC Championship and will not be fully recovered by the start of the season. The team signed veteran Lito Sheppard, who was cut by the Jets during the offseason, but he hasn't done enough to earn the starting job.
The team started second-year player Asher Allen in the second preseason game against San Francisco, but his play wasn't very effective. Allen might be a better fit as the nickel back, which is where he'll probably end up given that Benny Sapp was traded to Miami.
For the third preseason game, the Vikings will be starting rookie Chris Cook, the player taken with the team's first pick in the draft. Cook has displayed a great deal of athleticism since joining the team and even coach Brad Childress expressed that he has progressed faster than expected. Cook suddenly finds himself in the mix to win the starting job opposite Antoine Winfield.
Whether it be Cook or Sheppard, someone will have to hold down the right corner position and be effective or the team's secondary could be in trouble.