The Tampa Bay Rowdies qualified for the playoffs by virtue of winning the Eastern Division with 135 points. The point total earned them the number 2 seed and the right to host all preliminary rounds of the playoffs. The Rowdies defeated the Toronto Metros-Croatia in the quarterfinal match, 1–0, on August 13, 1975. Three days later they dispatched the Miami Toros, 3–0, in their semifinal game played on August 16, 1975, to advance to the finals.
The Portland Timbers qualified for the playoffs by virtue of winning the Western Division with 138 points. The point total earned them the number 1 seed and the right to host all preliminary rounds of the playoffs. The Timbers defeated the Seattle Sounders in the quarterfinal match, 2–1, in sudden death overtime on August 12, 1975. Five days later they beat the St. Louis Stars, 1–0, in a semifinal game played on August 17, 1975, to advance to the finals.