I think Football rules should be changed to stop substitution once the 4th official had flashed the stoppage time. Fulham unsportingly substituted during the final moments to prevent their point when Lamps almost scored. Unless there is an injury, every effort to "cheat" should be discouraged. (sic)

They don't need to replace - the FA just need to make sure refs enforce the minimum of 30 seconds of extra time per sub. It is a written rule but refs rarely enforce it.