CREATE TABLE table_15986020_3 (opponents VARCHAR, oilers_points VARCHAR)
SELECT opponents FROM table_15986020_3 WHERE oilers_points = 21
คะแนนรวมของฝ่ายตรงข้ามในเกมนี้คือเท่าไรที่ Oilers ได้ 21 คะแนน?
What was the total opponents points for the game were the Oilers scored 21?