CREATE TABLE table_64533 ("Game" FLOAT, "Date" TEXT, "Opponent" TEXT, "Score" TEXT, "Record" TEXT)

Who did the Hawks play on 12/21/1973?
SELECT "Opponent" FROM table_64533 WHERE "Date" = '12/21/1973'
SELECT "Opponent" FROM "table_64533" WHERE "Date" = '12/21/1973'