CREATE TABLE table_204_135 (id DECIMAL, "position" DECIMAL, "club" TEXT, "played" DECIMAL, "points" DECIMAL, "wins" DECIMAL, "draws" DECIMAL, "losses" DECIMAL, "goals for" DECIMAL, "goals against" DECIMAL, "goal difference" DECIMAL)

what team had the worst goal difference in the league ?
SELECT "club" FROM table_204_135 ORDER BY "goal difference" LIMIT 1
SELECT "club" FROM "table_204_135" ORDER BY "goal difference" NULLS FIRST LIMIT 1