Triple option teams use a “count” system in which they literally count the defenders to the play side in order to determine the following: who is the Dive Key (#1); who is the Pitch Key (#2); and, who is the primary run support player (#3)?
It is very important that the QB, Play Side A-Back, and the Play Side WR know who is who so that they will know what their assignment is. By definition, #1 is the first defensive lineman on or outside the play side OT (note: some schemes do not include a 4i D-Lineman to be #1 as they think this is too tough a read for the QB); #2 is defined as the “next” defensive player outside of #1 (note: some schemes read “the stack” while other teams refuse to read the stacked LB as #2); and finally, by definition, #3 is the primary run support defender (usually the next defensive player outside of #2). Usually, #3 will be either a safety of a LB.
Just to reiterate, it is very important that the players on offense know who each of these numbered defenders are so that they will all be on the same page running the base triple play!