CREATE TABLE table_48846 ("Result" TEXT, "Opponent" TEXT, "Method" TEXT, "Date" TEXT, "Round" FLOAT)

Which Round has a Method of ko, and a Date of 1958?
SELECT MIN("Round") FROM table_48846 WHERE "Method" = 'ko' AND "Date" = '1958'
SELECT MIN("Round") FROM "table_48846" WHERE "Date" = '1958' AND "Method" = 'ko'