Pitchers with a difference of at least 1 run between their ERA and FIP ERA for qualifying seasons

I got the data from Fangraphs and looked at all seasons since 1900. Someone mentioned Carl Lundgren on Twitter and in 1907 he had a 1.17 ERA and a 2.70 FIP (BBRef has 2.73). That seems like a big difference. So I wondered what would be the largest.

Table 1 below has the top 25 in what we could call good luck. Guys who had an ERA below their FIP. I did 26 because there was a tie for 25th.

Table 1

Rank	Name	Season	ERA	FIP	FIP - ERA
1	Sammy Stewart	1981	2.32	4.11	1.79
2	Steve Trachsel	1996	3.03	4.81	1.78
3	Hal McKain	1929	3.65	5.37	1.72
4	Bump Hadley	1939	2.98	4.69	1.71
5	Steve Swetonic	1932	2.82	4.43	1.61
6	Ryan Franklin	2003	3.57	5.17	1.6
7	Elmer Dessens	2002	3.03	4.61	1.58
8	Tim Wakefield	1995	2.95	4.53	1.58
9	Dakota Hudson	2019	3.35	4.93	1.58
10	John Candelaria	1977	2.34	3.9	1.56
11	Al Leiter	2004	3.21	4.76	1.55
12	Carl Lundgren	1907	1.17	2.7	1.53
13	Bucky Walters	1939	2.29	3.81	1.52
14	Doug Fister	2014	2.41	3.93	1.52
15	Jeremy Hellickson	2012	3.1	4.6	1.5
16	Jeremy Hellickson	2011	2.95	4.44	1.49
17	Pat Mahomes	1994	4.73	6.21	1.48
18	Gene Bearden	1948	2.43	3.89	1.46
19	Rickey Clark	1967	2.59	4.02	1.43
20	Ted Lyons	1935	3.02	4.44	1.42
21	Rip Collins	1929	4	5.42	1.42
22	Charlie Wagner	1941	3.07	4.47	1.4
23	J.A. Happ	2009	2.93	4.33	1.4
24	Jim Turner	1937	2.38	3.77	1.39
25	Jerry Ujdur	1982	3.69	5.08	1.39
26	Lance Lynn	2017	3.43	4.82	1.39

So Lundgren is fairly high at number 12. Now for the guys who had an ERA higher than their FIP ERA. This is Table 2.

Table 2

Rank	Name	Season	ERA	FIP	FIP - ERA
1	Jack Knott	1936	7.29	5.16	-2.13
2	George Caster	1940	6.56	4.52	-2.04
3	Hub Pruett	1927	6.05	4.11	-1.94
4	Chris Bosio	1987	5.24	3.38	-1.86
5	John Burkett	1998	5.68	3.89	-1.79
6	Joe Oeschger	1923	5.68	3.91	-1.77
7	Bert Blyleven	1988	5.43	3.66	-1.77
8	Ernie Wingard	1927	6.56	4.8	-1.76
9	Bobo Newsom	1942	4.73	2.99	-1.74
10	Ricky Nolasco	2009	5.06	3.35	-1.71
11	Early Wynn	1942	5.12	3.42	-1.7
12	Jack Lamabe	1964	5.89	4.21	-1.68
13	Pol Perritt	1913	5.25	3.59	-1.66
14	Rick Wise	1968	4.55	2.89	-1.66
15	Dan Griner	1913	5.08	3.43	-1.65
16	Elmer Myers	1917	4.42	2.77	-1.65
17	Bill Sherdel	1929	5.93	4.31	-1.62
18	Henry Keupper	1914	4.27	2.65	-1.62
19	Bob Rhoads	1903	4.76	3.16	-1.6
20	Les Sweetland	1930	7.71	6.11	-1.6
21	Gene Wright	1903	4.98	3.39	-1.59
22	Chief Bender	1915	3.99	2.4	-1.59
23	Dick Ruthven	1981	5.15	3.56	-1.59
24	Claude Willoughby	1926	5.95	4.37	-1.58
25	Jaime Navarro	1997	5.79	4.21	-1.58

Then I looked at what might account for these differences, both positive and negative. I looked at the batting average and slugging percentage these pitchers allowed with both no runners on base (None) and with runners on base (ROB). From casual observation, it often seems like pitchers that have extreme differences between their ERA and their FIP ERA also have extreme differences between what they do in None and ROB situations.

Also, their fielders may have affected their numbers. So I will later look at the Defensive Efficiency Rating of their teams. DER is the percentage of balls in play that are turned into outs

Table 3 below shows the AVG & SLG for the top 10 from Table 1 in both None and ROB situations. This data comes from BB Ref. as well as the DER data.

Table 3

Name	Season	None AVG	ROB AVG	None SLG	ROB SLG
Sammy Stewart	1981	0.224	0.226	0.319	0.296
Steve Trachsel	1996	0.257	0.203	0.488	0.294
Hal McKain	1929	0.294	0.252	0.404	0.367
Bump Hadley	1939	0.253	0.221	0.358	0.319
Steve Swetonic	1932	0.237	0.217	0.353	0.316
Ryan Franklin	2003	0.248	0.255	0.415	0.417
Elmer Dessens	2002	0.255	0.261	0.392	0.458
Tim Wakefield	1995	0.241	0.209	0.407	0.321
Dakota Hudson	2019	0.253	0.234	0.435	0.356
John Candelaria	1977	0.254	0.192	0.454	0.245

 

Most of these guys did much better in ROB cases. But not Stewart, Franklin or Dessens.

Table 4 below shows the DER of their teams in the given year and what the league average was (I am not sure the context of the league average helps explain anything). 

Table 4

Name	Season	Team DER	Lg. AVG
Sammy Stewart	1981	0.710	0.711
Steve Trachsel	1996	0.702	0.687
Hal McKain	1929	0.696	0.687
Bump Hadley	1939	0.730	0.687
Steve Swetonic	1932	0.702	0.691
Ryan Franklin	2003	0.721	0.694
Elmer Dessens	2002	0.690	0.695
Tim Wakefield	1995	0.682	0.690
Dakota Hudson	2019	0.706	0.689
John Candelaria	1977	0.711	0.698

 

Stewart and Franklin were on teams with fairly high DERs. So although they did not do any better in ROB cases, maybe the good fielding behind them explains their low FIP ERAs. But that is not the case for Dessens.

The following guys are the leaders in multiple seasons with an ERA at least 1 lower than their FIP ERA.
    
Tom Glavine     4
Bob Buhl     3
Bucky Walters     3

There were many with 2 such seasons. But none of the guys from the top 10 seasons are on this short list of 3 here. At most they could have had 2 such seasons, so they did not make a habit of it. I will look at these 3 guys later. Also, for guys who had an ERA at least 1 higher than their FIP ERA, no one did it more than twice.

Table 5 below shows the AVG & SLG for the top 10 from Table 2 in both None and ROB situations.

Table 5

Name	Season	None AVG	ROB AVG	None SLG	ROB SLG
Jack Knott	1936	0.305	0.348	0.419	0.512
George Caster	1940	0.325	0.303	0.525	0.466
Hub Pruett	1927	0.301	0.327	0.379	0.412
Chris Bosio	1987	0.266	0.290	0.422	0.406
John Burkett	1998	0.254	0.347	0.391	0.509
Joe Oeschger	1923	0.303	0.377	0.372	0.498
Bert Blyleven	1988	0.259	0.343	0.388	0.497
Ernie Wingard	1927	0.285	0.355	0.393	0.500
Bobo Newsom	1942	0.243	0.292	0.325	0.409
Ricky Nolasco	2009	0.223	0.317	0.351	0.562

Except for Caster, all of these guys did much worse in with ROB. Bosio had a lower SLG with ROB, but his ROB OPS was .753 vs. .731 with NONE on.

Table 6 shows their team's DER along with the league DER.

Table 6

Name	Season	Team DER	Lg. AVG
Jack Knott	1936	0.657	0.676
George Caster	1940	0.680	0.691
Hub Pruett	1927	0.663	0.687
Chris Bosio	1987	0.679	0.697
John Burkett	1998	0.668	0.686
Joe Oeschger	1923	0.668	0.681
Bert Blyleven	1988	0.699	0.702
Ernie Wingard	1927	0.666	0.684
Bobo Newsom	1942	0.676	0.706
Ricky Nolasco	2009	0.686	0.692

The team DER for these guys was generally low. It was just a bit low for Caster. But it still is surprising that given his AVG & SLG, he had such a high ERA.

Now for Glavine, Buhl and Walters. Table 7 shows their stats for the years they qualified.

Table 7

Name	Season	ERA	FIP	FIP - ERA
Bob Buhl	1957	2.74	3.95	1.21
Bob Buhl	1959	2.86	3.88	1.02
Bob Buhl	1960	3.09	4.1	1.01
Bucky Walters	1939	2.29	3.81	1.52
Bucky Walters	1940	2.48	3.84	1.36
Bucky Walters	1944	2.4	3.41	1.01
Tom Glavine	1997	2.96	3.96	1
Tom Glavine	1998	2.47	3.5	1.03
Tom Glavine	2001	3.57	4.77	1.2
Tom Glavine	2002	2.96	4.2	1.24

Table 8 shows the AVG & SLG for these 3 guys

Table 8

Name	Season	None AVG	ROB AVG	None SLG	ROB SLG
Bob Buhl	1957	0.267	0.213	0.369	0.296
Bob Buhl	1959	0.248	0.236	0.367	0.359
Bob Buhl	1960	0.242	0.211	0.416	0.271
Bucky Walters	1939	0.217	0.224	0.318	0.325
Bucky Walters	1940	0.220	0.220	0.316	0.329
Bucky Walters	1944	0.210	0.231	0.263	0.315
Tom Glavine	1997	0.240	0.204	0.340	0.322
Tom Glavine	1998	0.245	0.228	0.348	0.291
Tom Glavine	2001	0.277	0.236	0.420	0.347
Tom Glavine	2002	0.281	0.206	0.470	0.264

For Buhl & Glavine we can see that they did much better with ROB. But not Walters. So a surprise there but the next table shows he had good defense behind him, although it does not seem like it would make that much difference.

Table 9 shows the DER for these 3 guys.

Table 9

Name	Season	Team DER	Lg. AVG
Bob Buhl	1957	0.717	0.706
Bob Buhl	1959	0.703	0.701
Bob Buhl	1960	0.709	0.703
Bucky Walters	1939	0.708	0.695
Bucky Walters	1940	0.730	0.701
Bucky Walters	1944	0.731	0.707
Tom Glavine	1997	0.700	0.688
Tom Glavine	1998	0.700	0.689
Tom Glavine	2001	0.702	0.693
Tom Glavine	2002	0.712	0.695

For his entire career, Glavine had a .256 AVG and .384 SLG with NONE on and a .260 AVG and .369 SLG with ROB. I expected to see bigger differences and that his AVG with ROB would be lower.