Instructions
Experiment with base formations. If you find your favorite team being carved open time after time, adjust the base formation to something more defensively minded. "FIFA" has programmed formations with three, four or five defenders, and though the five-defender technique is strategically negative, an extra body at the back will stop other teams breaking you down so easily. If you find your team being opened up too easily, change your formation midgame, even if you don't have the best players on the field for the specific formation. Sometimes just having bodies in the right spaces makes all the difference.
Manually manage formation settings. "FIFA" allows you to customize your formation settings, including giving individual players tracking assignments, man-marking and movement guidelines. By default, certain players --- especially the wide backs --- are programmed to run forward. In the advanced formation menu, you can edit the movement of each player. Instead of having them charge forward, direct the arrows back and inward to narrow the pitch. You can then assign general marking to your defenders (and defensive midfielders) to have them track opposition forwards (and attacking midfielders).
Build your team around players with high defensive attributes. A good back line consists of players with decent pace (70 or higher), size and heading ability (70 or higher) to deal with long balls over the top and crosses in. Buy players in the transfer window who meet these criteria. You can search for players by attribute and type; try to find players with defensive leadership qualities.
Run a high line. It's a dangerous policy against crafty teams, but setting your defensive strategy to aggressively attempt the offside trap can catch other teams out, stop quick breakaways and negate dangerous through balls. The downside is that you may occasionally get caught with a defender out of position, and a long one-on-one will develop against your keeper.
Control defenders wisely. In game play there are two tackle/pressure buttons. The specific button varies depending on the platform and controller configuration, but the controls are named "tackle" and "pressure (second defender)." Pressing latter button calls another defender toward the opposition player on the ball, which can be effective for dealing with a single attacker but which pulls your players out of formation to create gaps in your back line. Try to avoid using the second tackle button, especially on the higher difficulty settings, as smart passing teams will expose the space left by the second defender.