CREATE TABLE table_17641 ("Record" CLOB, "Date and Time" CLOB, "Competition" CLOB, "Home or Away" CLOB, "Opponent" CLOB, "Score" CLOB)

Who was the opponent during the biggest defeat?
SELECT "Opponent" FROM table_17641 WHERE "Record" = 'Biggest defeat'
SELECT "Opponent" FROM "table_17641" WHERE "Record" = 'Biggest defeat'