A defensive maneuver in which one or more linebackers or defensive backs, who normally remain behind the line of scrimmage, instead charge into the opponent's backfield. However, in the 3-4 defense, one linebacker typically rushes the passer with the three down linemen.
Blisters are commonly caused by friction from tight shoes, herpes, chicken pox, poison ivy and allergic reactions. More uncommon are disorders that only cause blisters on the hands and feet. See your doctor for an accurate diagnosis if you have blisters on your hands and feet, particularly from an unknown cause.
Most people have had a blister at one time or another. Blisters commonly form on the feet or hands and are usually the result of rubbing or pressure concentrated to a specific area, like upon wearing a new pair of shoes for the day. Blisters may also be the result of a virus or other skin condition.