Here are instructions on how to play the latest edition of Football Manager in Steam's Offline mode correctly.

Playing Football Manager in Steam's Offline Mode has changed. Here's the proper way to stop your game by asking to connect back online.
Football Manager will need Internet access for its activation process because Steam is a network-based platform.
Football Manager players that do not want Steam to connect to the Internet can launch the Steam client in ‘Offline Mode’, after Football Manager installation.
The game will require internet access only to apply game updates or Steam's, or playing network games or use any of the uploading features to Steam's Workshop, that are in Football Manager.
1) Start Steam whilst connected to the Internet. Make sure that the “Remember my password” box on the login window is checked.
2) Verify that all game files are completely updated and that there are no current downloads on Steam (‘’Library’ -> ‘Downloads’).
3) Launch the game(s) you would like to play offline to verify that there are no further updates to download. Shut the game(s) down and return to Steam once you have confirmed that the game(s) can be played.
4) Go to ‘Steam’ -> ‘Settings’ and ensure that the “Don’t save account credentials on this computer option is NOT selected.
5) Click on the top left ‘Steam’ menu and select ‘Go Offline’.
6) Select ‘Restart in Offline Mode’. This will restart the Steam client and it will no longer connect to the Internet when it is launched.
If you would like to reconnect Steam to the Internet in the future to download game updates, activate new products or play multiplayer modes on your games, please select ‘Go Online from the top left ‘Steam’ menu.
Football Manager players that do not want Steam to connect to the Internet can launch the Steam client in ‘Offline Mode’, after Football Manager installation.
The game will require internet access only to apply game updates or Steam's, or playing network games or use any of the uploading features to Steam's Workshop, that are in Football Manager.
Play Football Manager in Steam's Offline Mode, please follow these instructions:
‘Go Online’ Again
If you would like to reconnect Steam to the Internet in the future to download game updates, activate new products or play multiplayer modes on your games, please select ‘Go Online from the top left ‘Steam’ menu.