Viking cornerback Asher Allen has retired from the NFL at the age of 24. Head Coach Leslie Frazier announced Wednesday of the decision made by Allen and said he was surprised to hear that Allen was retiring. He didn't get into the specifics as to why he is retiring. Allen started 9 games and appeared in 12 games for the Vikings in 2011. He missed some time due to a concussion and a shoulder injury. Frazier says Allen's decision is not related to injuries.