Runs Allowed measures the total number of runs scored against a pitcher while they are in the game regardless of whether the run was considered an earned run or not.
More about Runs Allowed Leaders
Pitching runs allowed leaders give up the most number of runs over the course of the season. To lead the league in this statistic a pitcher must pitch poorly enough to allow a significant number of runs but not pitch so badly as to be removed from his team’s pitching rotation and not be given an opportunity to pitch more (and thus give up more runs). Pitching runs allowed leaders are often established veterans who may be having a down season, though the team may feel he will eventually begin pitching better or may be paying him a lot of money and may not yet be willing to admit that a pitcher’s contract is a “sunk cost”.