A tactic a quarterback uses to evade a defense's pass rush. A quarterback scramble occurs when the quarterback leaves the area protected by the offensive line and runs into the other areas of the field. A quarterback can scramble to avoid a sack, extend a play to give the downfield receivers more time to get open, or to attempt to gain yardages. Quarterback scrambles are unpredictable plays, because they tend to be unplanned and have a high risk to the quarterback, since the offensive line is not prepared to block in the new area the quarterback has entered.
A quarterback scramble is a valuable tool for a mobile quarterback because it allows him to create opportunities for his offense. There are a large number of reasons a quarterback might decide to scramble. Some quarterbacks will scramble if they see an open area in front of them and want to try to gain yards on a run, and sometimes a quarterback will scramble behind the line of scrimmage in order to avoid a sack and allow the receivers downfield to get away from the defense and increase the chance of a pass completion. Quarterbacks who are faster and more athletic tend to be more effective in scrambling situations, and those quarterbacks often have plays designed to give them an opportunity to use their legs as well as their arm.