There are eleven players per side in Cricket. The line-up of the cricket players is set before each innings and may not be changed without the consent of the opposing team’s captain. A substitute may field for the team mate only if the teammate is injured or ill. If a fielder has to leave for another legitimate reason and the opposing captain consents, the team may substitute for the player.
A cricket player who was substituted for, may return to bat, bowl or field. If he was gone for more than 15 minutes, however he must be on the field for the length of time he was gone before he may bowl. A runner may run for a batter who is ill or injured. He must wear the same protective equipment that the batter wears. The injured batter is out when his runner is put out.