Innings Pitched (IP) – Very straightforward. This represents the number of innings pitched by that particular pitcher. Since pitchers can be removed in the middle of an inning, you’ll sometimes see a fraction (or decimal) reported. Oddly, when reported as a decimal, the decimal represents how many (of the three possible outs in an inning) the pitcher pitched. So, if a pitcher pitched five full innings, then is pulled from the game with one out recorded in the sixth, his IP for that game would be reported as 5.1.
Hits (H) – Again, very simple. The number of hits opposing batters had against this pitcher.
Runs (R) – The number of total runs given up by this pitcher. Note that a run will be counted against a pitcher even if the pitcher has been replaced when the run actually scores, if the baserunner who scores was on base because he made it safely to first while that pitcher was pitching.
Earned Runs (ER) – An earned run is a run counted against a pitcher that did NOT occur because of an error or passed ball.
Earned Run Average (ERA) – This statistic is meant to be a way to fairly compare pitchers’ effectiveness. Here’s the formula.
(ER x 9)/IP
Walks (BB) – BB is short for Base on Balls. The number of times the pitcher allowed batters to reach first base by throwing four balls during an at-bat.
Wins (W) – This is the number of games in which the pitcher was pitching while his team took the lead and went on to win.
Losses (L) – This is the number of games in which the pitcher was pitching while the opposing team took the lead, never lost the lead, and went on to win.
Saves (S) – This statistic has a few rules associated with it. It is meant to show how many times a pitchers helped your team keep the lead and win in the late innings. But stats wouldn’t be stats without some exacting rules. Here are the details. It is number of games where the pitcher enters a game with his team in the lead, finishes the game without surrendering the lead, is NOT the winning pitcher (see the Wins definition), AND at least one of the following are true:
1. The lead was three runs or less when the pitcher entered the game.
2. The potential tying run was on base, at bat, or on deck.
3. The pitcher pitched three or more innings.
Walks and Hits per Inning Pitched (WHIP) – This is another statistic meant to give a way to compare the effectiveness of one pitcher versus another. Here’s the formula:
(BB + H)/IP