CREATE TABLE table_5408 ("Date" TEXT, "Venue" TEXT, "Score" TEXT, "Result" TEXT, "Competition" TEXT)

What was the date of the friendly competition with a score of 4-0?
SELECT "Date" FROM table_5408 WHERE "Competition" = 'friendly' AND "Score" = '4-0'
SELECT "Date" FROM "table_5408" WHERE "Competition" = 'friendly' AND "Score" = '4-0'