CREATE TABLE table_39263 ("Date" TEXT, "Opponent" TEXT, "Score" TEXT, "Loss" TEXT, "Save" TEXT)

What is the score of the game on September 13 when the Expos were the opponent?
SELECT "Score" FROM table_39263 WHERE "Opponent" = 'expos' AND "Date" = 'september 13'
SELECT "Score" FROM "table_39263" WHERE "Date" = 'september 13' AND "Opponent" = 'expos'