To get this achievement you need to use the new feature on Fifa called quick sub. The quick sub allows you to sub a player on without pausing the game. You need to set it up before the game by going into team management and pressing and holding RT then choosing who you would like to quick sub on with A. Once you get into a game you can wait till you concede or just score an own goal, but a soon as the ball hits the net hold RT again and press A. Your sub will now appear on the pitch and the achievement is yours.
If you would like a video guide for this I will leave mine below