Table: t_1969_vfl_match
Columns: home_team
home_team_score
away_team
away_team_score
venue
crowd
date

Question: What was the smallest crowd during a game where the home team scored 12.9 (81)?
SQL: SELECT MIN("crowd") FROM t_1969_vfl_match WHERE "home_team_score" = '12.9 (81)'