CREATE TABLE table_43572 ("Result" TEXT, "TUF Competitor" TEXT, "Opponent" TEXT, "Method" TEXT, "Event" TEXT, "Date" TEXT)

when is the opponent lyoto machida?
SELECT "Date" FROM table_43572 WHERE "Opponent" = 'lyoto machida'
SELECT "Date" FROM "table_43572" WHERE "Opponent" = 'lyoto machida'