No matter how far ahead of your opponent you are in FIFA 18, don't put the controller down. Someone playing the FIFA 18 closed beta has found this out the hard way.
In one particular game, a player was ahead of their opponent 11 to 0. With 10 minutes left in the game, the winning player decided to take a break and grab a bite to eat. When he came back, he found out the game had been forfeited due to inactivity, costing him the match. If you want that win, no matter how great you're doing, make sure you play the entire time!