Designated HitterJuly 07, 2005
Ranking the Best Pitching Seasons Ever
By Cyril Morong

What was the best pitching season ever? We could look at the lowest ERA, but in some eras, ERAs were naturally low, like in the deadball era before 1920 when there were many seasons with ERAs under 2.00. We could look at the seasons with the most wins or highest winning percentages, but those are determined not just by the quality of the pitching but also by the run support a pitcher gets.

We could get around this problem by comparing a pitcher's ERA to the league average. Two pitchers might be judged equal if their ERAs are both 25% below the league average. Pitcher A might have an ERA of 3.00 with the league average being 4.00 while pitcher B has an ERA of 2.25 in a league with an average ERA of 3.00.

But a problem that often emerges in this approach is that the best seasons often come when runs per game were very high or very low. In extremely high scoring seasons, it may be easier to go far below the league average since the average is so high. Extremely low scoring seasons might increase the chances of any pitcher having a very low ERA.

One possible solution is to compare the best pitcher in the league to the other good pitchers in the league. If it is easy for one pitcher to go far below the league average, it should be easy for a few others. By comparing the league leader in ERA (or any measure of pitching quality) to the other very good pitchers, the problem mentioned above might be lessened.

ERA can also be affected by the home ballpark of the pitcher. So in addition to comparing the best pitchers to other good pitchers, their performance should be adjusted for park effects. Pitchers in high scoring parks will have their runs allowed adjusted downward and vice versa.

One measure that allows for this is called RSAA. It comes from the Lee Sinins Sabermetric Encyclopedia, a commercial database that can be purchased by any baseball fan. Here is the definition: "Runs saved against average. It's the amount of runs that a pitcher saved vs. what an average pitcher would have allowed."

I looked at how the RSAA of league leaders since 1900 compared to the average RSAA of the pitchers who finished 2-10 (hence, the idea of comparing top pitchers to other good pitchers). For example, Walter Johnson had 75 RSAA, meaning he allowed 75 runs less than the average pitcher. The next 9 best pitchers in 1913 averaged 25.56. So Johnson was 49.44 better.

But having, say, 30 more RSAA than the next best nine pitchers might mean more in a low scoring year than a high scoring year. In a low scoring year it will take a lower number of runs to add one over the course of a season. But how many? I used the formula which says it takes 10 times the square root of the number of runs scored per inning by both teams (found in Total Baseball, 5e). If each team scores .5 runs per inning, the total is one. The square root is 1 and 10 times that is 10, so it would take 10 additional runs over the course of a season to win one more game. The Lee Sinins Sabermetric Encyclopedia can call up the top 10 each season in RSAA.

Who were the top pitchers according to this method? The top 10 in the AL are listed below:

Pitcher	         Year	RSAA	RSAA 	Diff*	R/W	Extra Wins
Walter Johnson	1913	75	25.56	49.44	9.39	5.26
Pedro Martinez	2000	77	24.56	52.44	10.89	4.81
Lefty Grove	1931	75	26.67	48.33	10.73	4.50
Lefty Grove	1932	75	26.70	48.30	10.81	4.47
Walter Johnson	1912	74	29.56	44.44	10.02	4.44
Walter Johnson	1918	56	16.92	39.08	8.97	4.36
Cy Young	         1901     72	25.11	46.89	11.08	4.23
Pedro Martinez	1999	71	28.11	42.89	10.87	3.95
Lefty Grove	1926	62	23.33	38.67	10.34	3.74
Hal Newhouser	1945	59	24.44	34.56	9.34	3.70
Lefty Grove	1936	70	29.78	40.22	11.32	3.55


In 1913 it took 9.39 runs to win one more game. Since 49.44/9.39 = 5.26, Johnson added 5.26 more wins than the average of the next best nine pitchers in the league (I have eleven pitchers here--Hal Newhouser's season was a war year, when many good pitchers may have been in the military).

For the NL, the top 10 were:

Pitcher	         Year	RSAA	RSAA 	Diff*	R/W	Extra Wins
Grover Alexander	1915	69	15.80	53.20	9.00	5.91
Dolf Luque	1923	66	24.00	42.00	10.40	4.04
Bob Gibson	1968	56	21.78	34.22	8.72	3.93
Greg Maddux	1995	64	24.80	39.20	10.17	3.86
Christy Mathewson	1905	61	25.33	35.67	9.62	3.71
Dwight Gooden	1985	58	22.75	35.25	9.51	3.71
Dazzy Vance	1930	64	22.36	41.64	11.33	3.68
Carl Hubbell	1933	52	18.10	33.90	9.44	3.59
Dazzy Vance	1924	56	20.78	35.22	10.07	3.50
Bucky Walters	1939	58	23.11	34.89	9.99	3.49


One problem can be seen--if you know some baseball history--is that we still see the best pitching performances coming from what are generally fairly high or fairly low scoring years. I really don't know the solution. Comparing players using standard deviations instead of simple averages might be better. I ran this study and ranked pitchers in ERA based on how many standard deviations below the average of all qualifying pitchers they were. Pedro Martinez in 2000 was the best, being 3.79 SDs below average.

Looking at ERA has an advantage over RSAA, since it only includes earned runs whereas RSAA includes both earned and unearned runs. Unearned runs may not be the fault of the pitcher. I also looked at the best ERAs relative to the 2-5 pitchers each year.

But both RSAA and ERA are, in part, determined by the quality of the fielding behind the pitcher. In his Win Shares methodology, Bill James attempted to rate pitchers solely on their contribution to winning, independent of the fielders. Using the electronic Win Shares database, I found the best seasons by taking the league leader and seeing how many Win Shares he had as percentage of the pitchers who finished 2-5.

Pitcher	  Year	WS	Ratio
Alexander	  1915	43.32	1.87
Maddux	  1994	25.96	1.86
W. Johnson 1913	50.28	1.81
Alexander  1917	39.11	1.77
Grove	  1931	41.83	1.74
Walsh	  1908	46.62	1.74
Alexander  1916   41.95    1.72
Maddux	  1995	29.87	1.72
Vance	  1924	35.57	1.68
W. Johnson 1915	39.34	1.67
Carlton	  1972	40.38	1.67
Martinez	  2000	28.86	1.64
Chesbro	  1904	51.80	1.63
Luque	  1923	38.97	1.63
Walters	  1939	34.50	1.59
Gibson	  1968	36.36	1.52
Clemens	  1997	31.66	1.52
Martinez	  1999	26.89	1.52
Perry	  1972	39.04	1.50

The same pitchers seem to be near the top on all of these lists (including the lists at the links given above). There could be a problem that the quality of pitchers they are being compared to is relatively low (which might explain why they all do so well in simple comparisons to the league average as well). Maybe some years just did not have many good pitchers. I don't know how that could be determined. One suspicion I have about some of Pedro Martinez's good years is that there were no other very good pitchers. Roger Clemens was in decline. Randy Johnson was traded to the NL. But maybe the same could be said about Bob Gibson in 1968. Sandy Koufax was gone. Tom Seaver had yet to hit his prime. Maybe it could be said about any of these pitchers.

Some pitchers who stand out even among this crowd are Walter Johnson, Grover Cleveland Alexander, Greg Maddux, and Pedro Martinez. They each have two consecutive seasons that both appear near the top of these lists. They proved what they did was no fluke.

Cyril Morong teaches economics at San Antonio College and is a lifelong White Sox fan. A member of SABR since 1995, his articles have appeared in The Baseball Resarch Journal, By the Numbers and on line at The Chicago Sports Review.

[Additional reader comments and retorts at Baseball Primer.]


Great post. I would be curious to see, by measuring the same way, the best rotation in history or perhaps how those teams in those years did with one (or more) very, very good pitching seasons behind them.

I wonder how Cy Falkenberg would have pitched in the AL or NL in 1914?

Garth: Thanks. It might be worthwhile to look at the best pitching teams. But right now I don't have time.

Steve: Falkenberg's best RSAA after his 81 in 1914 is 27 in 1913 in the AL. Other than that, he was generally negaitve or very low. Maybe he would have done very well in the AL that year. We have seen some pitchers have one great year (can't think of any right now). In the new Baseball Encyclopedia, Pete Palmer gives the Federal League players something like 80% of their value when ranking them all-time. Even 80% of 81 would be a great year. I just have no idea how to figure this.

Where did you get an electronic Win Shares database. I've been looking all over trying to find one. Any info would be greatly appreciated!

You need to go to the STATS, INC website. It is actually called "Win Shares - Digital Edition" Go this site

Thanks for your help - are those updated through 2004 or just 2002?

hello folks, A friend and I are having an ongoing discussion he says NOLAN RYAN is the best and I say he is among the top 15-or 20 ???Any input would be most welcome thanx charlie

Nolan Ryan is not number 1. Maybe top 20. As far as the stats of each particular era go, my best-remembered pitching performances would have to be Gooden's '85, Gibson's '68, Pedro's '99, Koufax's '65, and on a personal admiration level, Hersheiser's '88.

I'm wondering, would it possible for a No. 2 in a certain year be better than a No. 1 in another year?

Yes, that would be possible. The best pitching seasons have typically been clumped together, particularly in the Deadball Era and in a year like 1968. However, this study is adjusting for such effects by analyzing the best pitching seasons relative to the league average as opposed to absolute terms.

I've always been convinced that Martinez's 2000 season was far and away the best pitched season ever. As you've shown very nicely, his numbers stack up with all the best pitched seasons, no matter how you adjust them (or even if you don't). Not only that, but he certainly received no aid from his home park or the mediocre defense behind him.
There's one stat for him that always stands out to me: his 0.74 WHIP. That season, Martinez allowed an absurdly low number of baserunners, an indication of his dominance. I believe I once read that only one other single-season WHIP of any pitcher, ever, even broke 0.80.

Here is the top 20 single-season Baserunners/9 IP:

BASERUNNERS/9 IP              YEAR   BR/9 IP   
1    Pedro Martinez           2000     7.22   
2    Walter Johnson           1913     7.26   
3    Addie Joss               1908     7.31   
4    Charlie Sweeney          1884     7.35   
5    Christy Mathewson        1909     7.45   
6    Greg Maddux              1995     7.47   
7    Ed Walsh                 1910     7.47   
8    Christy Mathewson        1908     7.60   
9    Three Finger Brown       1908     7.72   
10   Denny Driscoll           1882     7.79   
11   Sandy Koufax             1965     7.82   
12   Grover C Alexander       1915     7.83   
13   Bob Gibson               1968     7.88   
14   Silver King              1888     7.88   
15   Juan Marichal            1966     7.89   
16   Dave McNally             1968     7.91   
17   Ed Walsh                 1908     7.91   
18   Sandy Koufax             1963     7.96   
19   Luis Tiant               1968     7.98   
20   George Bradley           1876     7.98   

Martinez and Maddux are the only pitchers in the top ten who accomplished their feat in the post-Deadball era.

Why isn't Ron Guidry even mentioned for his 78 season? In my opinion, this whole article is slanted because of this omission. 25-3 record, ERA of 1.74, 9 shutouts, 250 K's, and MOST importantly, a world series ring!

Where is Koufax's 63 season?

Koufax in 1963 actually was second in the league to Dick Ellsworth. You have to remember that RSAA is park adjusted and Koufax pitched in a very good pitcher's park. Ellsworth pitched in Wrigley Field. Koufax had an ERA of 1.88 that year but Ellsworth is not too far behind at 2.10. He only beats Koufax in RSAA by a 43-40 margin.

You also have to remember that each league leader in RSAA is judged against the next best 9 pitchers for that season. Then even that is adjusted for how many runs it took that year to win one game. Koufax's 1966 season is 23rd among NL pitchers (2.89 wins better than pitchers 2-10-Koufax had 58 RSAA that year). Ellsworth's 1963 season is 57th.

Guidry's 1978 season was 35th among AL pitchers.

Here are the RSAA leaders in the 1963 NL and the 1978 AL. To make my list, a pitcher would have to really dominate the next best 9 guys. You have to put things in context.

1963 NL
1 Dick Ellsworth 43
2 Sandy Koufax 40
3 Curt Simmons 28
4 Larry Jackson 27
T5 Bob Friend 26
T5 Juan Marichal 26
7 Warren Spahn 21
T8 Joe Nuxhall 19
T8 Ron Perranoski 19
T8 Bob Veale 19

1978 AL
1 Ron Guidry 58
2 Mike Caldwell 53
3 Jon Matlack 40
4 Dennis Eckersley 32
5 Jim Palmer 30
6 Larry Gura 27
7 Dave Goltz 26
8 Goose Gossage 25
9 Lary Sorensen 24
10 Bob Stanley 23

I have also tried to rank the best seasons using defense independent stats (DIPS ERA). Go to:

I used several different methods and both Guidry and Koufax have some good rankings.