CREATE TABLE table_57681 ("Res." TEXT, "Record" TEXT, "Opponent" TEXT, "Method" TEXT, "Event" TEXT, "Round" FLOAT, "Time" TEXT)

How many rounds have an Opponent of sakae kasuya?
SELECT COUNT("Round") FROM table_57681 WHERE "Opponent" = 'sakae kasuya'
SELECT COUNT("Round") FROM "table_57681" WHERE "Opponent" = 'sakae kasuya'