A single game often requires multiple pitchers, including the starting pitcher and relief pitcher(s). Pitchers are substituted for one another like any other player (see above), and the rules do not limit the number of pitchers that can be used in a game; the only limiting factor is the size of the squad, naturally. In general, starting pitchers are not used in relief situations except sometimes during the post-season when every game is vital. If a game runs into many extra innings, a team may well empty its bullpen. If it then becomes necessary to use a "position player" as a pitcher, major league teams generally have certain players designated as emergency relief pitchers, to avoid the embarrassment of using a less skillful player. In baseball's early years, squads were smaller, and relief pitchers were relatively uncommon, with the starter normally remaining for the entire game unless he was either thoroughly ineffective or became injured; today, with a much greater emphasis on pitch count, over the course of a single game each team will frequently use from two to five pitchers. In the 2005 ALCS, all four of the Chicago White Sox victories were complete games by the starters, a highly noteworthy event in the modern game.