Madden NFL 10 Cheats :
Secret - All stats are player stats are 99 in Play Now Mode
First click on the EA icon, then go to Rosters, i think it is, then click on "View Rosters"
Then click a team and then click a player, then click "Stats and Info" Now you can mess around with the players stats!
NOTE: The stats will be reset if you go on "Classic Modes"
Code - Cheat mode
Select "EA Extras" at the main menu. Select "Enter Game Code", then enter one of the following codes to activate the corresponding cheat function.