SELECT "Date" FROM table_33664 WHERE "Venue" = 'mcg'
What was the date of the match played at MCG?
CREATE TABLE table_33664 (
    "Home team" text,
    "Home team score" text,
    "Away team" text,
    "Away team score" text,
    "Venue" text,
    "Crowd" real,
    "Date" text
)