AFL Live

This one is easy enough. it does not require you to win the match. all you need to do is comlpete it.
set up a multiplayer game with you and 1 other controller on the same team. i set the quarters to 3 minutes to keep it quick. after starting the game, go and find something else to do for a few minutes or simply play to pass the time.
Remember that if you do leave the console you will have to return at the end of each querter to press A and go on to the next quarter.

this will pop at the end of the last quarter.

if you have another profile signed into the 2nd controller they will also get this achievement.

PS. i signed in a profile on the 2nd controller halfway through the game and they still got the chievo at the end.

You can actually do this during the course of playing through the game normally. This achievement will pop so long as you have two players on the same team at full time, so there's no need to start a game with 2 controllers. You can just add a 2nd controller to your team late in the 4th quarter of any match and this will pop.

What I had done to test this was start a game with one controller on each team, 3 minute quarters (I was doing this for the sake of getting a draw at the same time, figured I might as well). I let the game sit there, and then with 1 minute left in the 4th quarter, I paused, and switched player 2 to the same team as player 1. At the end of the match, No "I" in Team popped.