He asked to leave,there is nothing you can do there.
- Chelsea with Matic last year
- PSG with Verratti
- PSG with Cavani
- Barcelona with Mascherano
Ultimately, we dealt with Lichtsteiner properly, and what happened. He actually resigned.
You got to be prudent too. If a guy will leave for free in a year, reconsider, but if they're signed for 3 more years, tell them to shove it. By capitulating to players demands, you empower agents, and legitimize their BS.