As the player is paid by Liverpool then it will be Liverpool who dictate their fitness regimes
If a player gets injured when training then he gets injured - if he gets injured when he should be resting then that's a failing ( which is the exact point that is being made by Rodgers ) - the player it appears asked to be rested as per his fitness regime but that was ignored ( that is the point which is clearly being missed )
It makes zero difference who the player plays for
But its ok for L'pool to play a player for 5 mths who needed shoulder surgery? Where is the Duty of Care in that? Let's remember, the player could have exacerbated that injury during the rough and tumble of a game. Duty of Care when its suits... this isn't Victorian times, when employers could ride rough shod over its employees.
You can witter and whinge and whine as much as you like but if L'pool are willing to play someone who needed surgery...