As it is now, there is nothing much a user can do to prevent injuries. Even squad rotation fails (the 2 players injured as shown above were reserve players). There is either a flaw or something malfunctioning in this game or all this has been intentionally been programmed to occur as such so that users are forced to buy tokens or complete offers, else let their team suffer. But based on what I have seen so far about this game, it is more likely that this is intentional; greedy Nordeus.