CREATE TABLE table_name_21 (tournament VARCHAR, away_team VARCHAR, home_team VARCHAR)

What was the tournament where Japan was the home team and Mexico was the away team?
SELECT tournament FROM table_name_21 WHERE away_team = "mexico" AND home_team = "japan"
SELECT "tournament" FROM "table_name_21" WHERE "away_team" = "mexico" AND "home_team" = "japan"