Table schema:
CREATE TABLE table_name_3 (total_goals INTEGER, position VARCHAR, league_apps VARCHAR, total_apps VARCHAR)

Question: What is the fewest total goals scored for players with under 171 league appearances, 151 total appearances, and the DF position?
SQL: SELECT MIN(total_goals) FROM table_name_3 WHERE league_apps < 171 AND total_apps = 151 AND position = "df"