In gridiron football, a spike of the ball is the act of intentionally and forcefully throwing the ball to the ground. Most commonly, this takes the form of a celebration after a score (see below) or a play in which the quarterback intentionally throws a live ball at the ground.
Being an incomplete pass, a spike play stops the clock at the cost of exhausting a down without any gain or loss in yardage. It is principally used when a team is conducting a hurried drive late in a half, and the game clock is running after the previous play. Stopping the clock – particularly when the offense has no timeouts remaining or wishes to conserve timeouts – typically allows the offense more time to plan their next play without losing scarce game clock time.[1]
Running a spike play presumes there will be at least one play by the same team immediately afterward, so it cannot be done on fourth down, as it would result in a turnover.[2] Under NCAA, a minimum of three seconds must be on the clock for a spike play; otherwise, any spike after will result in the rest of the clock being run off.[3] This restriction does not apply in the NFL, where a legally-executed spike will stop the clock provided it is performed with at least one second on the clock.
A spike can only be legally performed when the passer is under center, performs the spike immediately after the snap in a single continuous movement, and when the game clock is running. Spiking at any other point while the ball is live is always intentional grounding regardless of pressure or location; this is called a delayed spike.[4]
In Canadian football, spike plays are legal but very rare. This is mainly because the clock always stops after the three minute warning after every play until the ball is spotted by the officials for the next play and also because a final play is always run at the end of each quarter whenever the game clock expires while the ball is dead, rendering spike plays unnecessary. Also, the offense in Canadian football only receives three downs instead of four.