CREATE TABLE table_6471 ("Date" CLOB, "Opponent" CLOB, "Score" CLOB, "Loss" CLOB, "Save" CLOB)

What Opponent played on the Date May 21?
SELECT "Opponent" FROM table_6471 WHERE "Date" = 'may 21'
SELECT "Opponent" FROM "table_6471" WHERE "Date" = 'may 21'