CREATE TABLE table_35890 ("Date" TEXT, "Competition" TEXT, "Opponents" TEXT, "Venue" TEXT, "Score" TEXT)

Who was the opponent at the League Cup competition with a score of 3-1?
SELECT "Opponents" FROM table_35890 WHERE "Competition" = 'league cup' AND "Score" = '3-1'
SELECT "Opponents" FROM "table_35890" WHERE "Competition" = 'league cup' AND "Score" = '3-1'