Ball / denominator lens
Possession needs a clock.
Three states divide this deliberately limited window. A percentage without its measured period can look more complete than the observation really is.
An interval, not a final score
Illustration 03 / 50 observed minutes18 of 50 min
27 of 50 min
5 of 50 min
Framework: FIFA Training Centre, Data analysis definitions (29 Jul 2024; accessed 26 Sep 2026). The 18/27/5 figures and derived shares are fictional, not FIFA match data or an Opta percentage.

Recorded
18 ÷ 50 gives 36% of this observed window in possession for Team A. The other two states use the same 50-minute denominator. The FIFA framework distinguishes possession, out of possession and ball in contest.
Still unknown
These minutes do not cover a whole match, describe chance quality or establish a winner. More possession alone does not establish either: FIFA Training Centre, How important is possession? (9 Nov 2023; tournament analysis, not a Nigeria finding).