Do Reliever Won-Lost Records Mean Anything in Modern Baseball?
A few days ago I posted here a poll question: Do the won-lost records of relievers mean anything in modern baseball? Do relievers who pitch well tend to have ANY better won-lost records than relievers who don’t pitch well? Or is the relationship even inverse, that relievers who pitch poorly are more likely to pick up wins?
This is a very simple study of a very simple question. . .took me about twenty minutes to do. I took the records of all pitchers:
a) since 1990,
b) who did not make a start,
c) and pitched at least 40 times in relief,
d) and had at least four decisions.
There are 1,835 such pitchers. These I sorted into three groups:
A) Winning Percentage over .600,
B) Winning Percentage of .400 to .600,
C) Winning Percentage under .400.
And I figued the performance averages for each group.
There were 670 relievers with winning percentages over .600, 570 with winning percentages of .400 to .600, and 595 with winning percentages under .400. These were the aggregate won-lost records of the groups:
Group A 3690-1514 .718
Group B 2409-2406 .500
Group C 1269-3071 .282
The answer is: the pitchers who had better won-lost records did pitch better, and the pitchers who pitched better did have slightly better won-lost records.
The games and innings pitched of the three groups were near the same—62 games, 68.0 innings for Group A, 63 games, 68.2 innings for Group B, and 61 games, 64.1 innings for Group C.
The strikeout/walk data was just a hair better for Group A—K/W of 57/26 for Group A, 57/27 for Group B, and 54/26 for Group C.
The pitchers in Group A got out 71% of the hitters they faced, in Group B 70%, and in Group C 69%. Each group faced about 300 batters per season.
The average ERA of Group A was 3.40, of Group B, 3.71, of Group C, 4.03. I looked at the league ERAs and ERAs relative to league just to make sure there wasn’t some distortion there, and there wasn’t.
I sorted the data by the other axis, so that Group A was the most effective pitchers (2.61 ERA), Group B the pitchers of middling effectiveness (3.68), and Group C the least effective (4.95). The winning percentages, by group, went .563, .496, and .458.
It is worth noting that the pitchers with the best winning percentages had an average of 22 Games Finished and 7 Saves, whereas the pitchers with .500 records had averages of 27 Games Finished and 9 Saves, while those with losing records had averages of 29 Games Finished and 12 Saves. In other words, use as a closer does increase a reliever’s liability for losses, and makes it more likely that he will post a losing record. But there are two things that cause losing records in relievers—being used as a closer, and ineffectiveness.
In modern baseball we don’t evaluate relievers by their won-lost records, and obviously we shouldn’t; I’m not suggesting that we move in that direction. But that’s not the question I was asking. What I was asking was this: has the nature of the modern bullpen rendered won-lost records for relievers wholly irrelevant, or are they still indicative of performance at some low level? And the answer is: they are still indicative of performance at a low but not terribly low level.