CREATE TABLE table_11800 ("Week" CLOB, "Date" CLOB, "Opponent" CLOB, "Result" CLOB, "Kickoff [a ]" CLOB, "Game site" CLOB, "Attendance" CLOB, "Record" CLOB)

Who was the opponent team on September 30, 1990?
SELECT "Opponent" FROM table_11800 WHERE "Date" = 'september 30, 1990'
SELECT "Opponent" FROM "table_11800" WHERE "Date" = 'september 30, 1990'