CREATE TABLE table_5237 ("Season" CLOB, "Tier" FLOAT, "Division" CLOB, "Pos." FLOAT, "Postseason" CLOB, "Cup Competitions" CLOB)

What is the lowest tier for a postseason result of quarterfinalist?
SELECT MIN("Tier") FROM table_5237 WHERE "Postseason" = 'quarterfinalist'
SELECT MIN("Tier") FROM "table_5237" WHERE "Postseason" = 'quarterfinalist'