11 players per team on field including 1 goalkeeper (Rule 2, Composition of Teams); Roster: typically 16-22 players for NCAA D1; up to 18 may be in match-day squad; Substitutions: unlimited and rolling (Rule 2 framework as modified by NCAA — distinct from FIFA limited subs); player exits, substit...
Why people argue about this
People often assume that unlimited substitutions at the 22.90-m line mean players can come on and off the field whenever they want, which leads to confusion about timing and strategy. The actual rule stipulates unlimited subs but with brief stoppages, so it's a fine balance between keeping the game moving and ensuring fair play.