How should a referee restart the game after stopping it for a violent tackle committed by a substitute during a penalty kick?

When a referee stops the game due to violent conduct by a substitute during a penalty kick, the appropriate course of action is to restart with a penalty kick for the opposing team. This is because the violent tackle committed by the substitute is considered a serious offense and interrupts the game in a manner that warrants a significant response.

In this scenario, the original penalty kick is deemed void because the offense occurs while the play is still active. Thus, the referee must ensure that the team that was fouled (in this case, the Red team) is given a fair opportunity to restart play. Awarding a penalty kick to the Red team serves as a direct consequence of the substitute's misconduct and helps to maintain fairness in application of the rules.

The other options do not adequately address the nature of violent conduct and its repercussions. Allowing a retake of the penalty kick or considering the kick successful fails to acknowledge the seriousness of the substitute's actions. Restarting with a free kick for the Blue team would not reflect the correct punishment for the violent behavior displayed, as it rewards the team that committed the foul. Therefore, the decision to restart with a penalty kick for the Red team aligns with the principles of enforcing discipline and ensuring fair play in the game.