also: ace backfield · single back · ace formation
Three different formations, and a blocking call on top of that. One running back, one receiver split to each side, or the Air Raid's base four-wide set, plus the ace block, which is a different thing entirely. A coach hearing it has to know whose ace.
3 meanings, all below. Jump to the one you heard.
A backfield with one running back in it. The word names the backfield and nothing else, so ace tells you where one player is and leaves the other four skill positions open.
One back is the most common backfield in modern football, because it is the one that frees five eligible receivers to be distributed. That is what makes 11 and 10 personnel the groupings they are.
single backpistol, personnel grouping, ace blockOne receiver split out to each side. Here the word counts receivers rather than backs. It belongs to a set of words that all do: doubles is two to each side, and a staff using ace this way will have a word for every distribution it runs.
So the same call tells two coaches two different things. One hears a backfield and one hears a receiver split, and neither of them is wrong.
doubles, tripsMike Leach's base set. Four receivers, one back, two to each side, and the two sides are deliberately not mirrors of each other: X and Y are on the line, H and Z are off it. Ace Rip is the modifier that makes them mirror.
This is where the word turns on itself. An Air Raid Ace has two receivers to each side, so by the counting sense above it is a doubles set. Two of the three meanings give the same formation two different names.
Air Raid, doubles**Ace is a backfield value in Playside's diagram editor**, which is where most of our users will meet the word. It is the first sense above.