CREATE TABLE table_55139 ("Competition" TEXT, "Current position / round" TEXT, "Final position / round" TEXT, "First match" TEXT, "Last match" TEXT)

When the final position/round is group stage, when is the last match?
SELECT "Last match" FROM table_55139 WHERE "Final position / round" = 'group stage'
SELECT "Last match" FROM "table_55139" WHERE "Final position / round" = 'group stage'