Best WAR per inning pitched in 2011

In 2011, there were 19 pitchers who pitched at least 50 innings and earned at least 3.5 WAR per every 100 innings pitched. (This was found by ensuring that WAR > 0.035 * IP). Who are they? It might surprise you.

Rk		WAR	IP	Age	Tm	G	GS	GF	SV	ERA	ERA+
1	Mike Adams	2.9	73.2	32	TOT	75	0	10	2	1.47	266
2	John Axford	2.7	73.2	28	MIL	74	0	63	46	1.95	200
3	Grant Balfour	2.2	62.0	33	OAK	62	0	15	2	2.47	165
4	Tyler Clippard	3.4	88.1	26	WSN	72	0	8	0	1.83	211
5	Jesse Crain	2.3	65.1	29	CHW	67	0	11	1	2.62	162
6	Scott Downs	2.2	53.2	35	LAA	60	0	10	1	1.34	285
7	Joel Hanrahan	2.9	68.2	29	PIT	70	0	59	40	1.83	209
8	Greg Holland	2.6	60.0	25	KCR	46	0	15	4	1.80	228
9	Jim Johnson	3.2	91.0	28	BAL	69	0	20	9	2.67	155
10	Josh Johnson	2.5	60.1	27	FLA	9	9	0	0	1.64	239
11	Craig Kimbrel	3.0	77.0	23	ATL	79	0	64	46	2.10	181
12	Ryan Madson	2.2	60.2	30	PHI	62	0	46	32	2.37	164
13	Eric O'Flaherty	3.7	73.2	26	ATL	78	0	5	0	0.98	389
14	Vinnie Pestano	2.2	62.0	26	CLE	67	0	20	2	2.32	172
15	J.J. Putz	2.1	58.0	34	ARI	60	0	52	45	2.17	182
16	Mariano Rivera	3.5	61.1	41	NYY	64	0	54	44	1.91	232
17	David Robertson	3.9	66.2	26	NYY	70	0	8	1	1.08	410
18	Jose Valverde	2.7	72.1	33	DET	75	0	70	49	2.24	183
19	Jonny Venters	3.7	88.0	26	ATL	85	0	10	5	1.84	206

Provided by Baseball-Reference.com: View Play Index Tool Used
Generated 11/10/2011.

What do these guys all have in common? They're all relievers, of course (save for Josh Johnson, who had an injury-shortened season.)

Seven of them were closers in 2011 and the rest were middle relievers (other than, again, Johnson.)

It's a bit surprising to me that there are no full-season starters on here. I wonder why? A couple of theories:

• The guys who made this list all performed at a very high level too difficult to maintain over, say, 200 innings.
• The guys who made this list were all utilized primarily in situations that benefited the accumulation of WAR.

Among active pitchers, minimum 200 IP, here are the only guys to average at least 3.5 WAR per 100 IP over their career:

Rk		WAR	IP	G	GS	GF	SV	ERA	ERA+
1	Jonathan Papelbon	17.1	429.1	396	3	334	219	2.33	197
2	Mariano Rivera	56.3	1211.1	1042	10	883	603	2.21	206
3	Joakim Soria	13.5	315.1	298	0	239	160	2.40	181

Provided by Baseball-Reference.com: View Play Index Tool Used
Generated 11/10/2011.

Yup....3 closers.

If we drop the bar to 2.5 WAR per 100 innings pitched, here are the active guys to clear that:

Rk		WAR	IP	G	GS	GF	SV	ERA	ERA+
1	Mike Adams	8.7	311.1	297	0	49	3	2.11	187
2	Francisco Cordero	21.4	785.1	753	0	557	327	3.17	145
3	Bobby Jenks	9.2	357.1	348	0	286	173	3.53	131
4	Jim Johnson	7.1	261.0	215	1	74	21	3.31	132
5	Josh Johnson	18.7	725.1	123	113	1	0	2.98	143
6	Joe Nathan	22.1	729.2	581	29	408	261	2.87	152
7	Hideki Okajima	6.3	246.1	261	0	44	6	3.11	149
8	Jonathan Papelbon	17.1	429.1	396	3	334	219	2.33	197
9	J.J. Putz	12.5	464.1	457	0	281	151	3.06	141
10	Mariano Rivera	56.3	1211.1	1042	10	883	603	2.21	206
11	David Robertson	5.2	202.0	204	0	46	3	3.03	147
12	Francisco Rodriguez	22.7	648.2	604	0	445	291	2.51	172
13	Takashi Saito	11.1	326.0	322	0	187	84	2.18	199
14	Joakim Soria	13.5	315.1	298	0	239	160	2.40	181
15	Brad Ziegler	6.9	252.0	246	0	72	19	2.43	174

Provided by Baseball-Reference.com: View Play Index Tool Used
Generated 11/10/2011.

Again, all relievers except for Josh Johnson, who has been almost exclusively a starter in his career. Although closers are well-represented on this list, there are plenty of middle relievers, too. This argues against the idea that it's a usage pattern allowing these guys to rack up WAR (since there are a bunch of different ways these guys were used.)

No, I tend to think it's the fact that such great performance is difficult to sustain over a large number of innings, and these guys are all fantastic pitchers who throw a relatively small number of innings each year. In fact, this is perhaps one of the better arguments I've heard about why relievers shouldn't be considered for Cy Young or the Hall of Fame--because their small number of innings does give them an advantage from a regression-to-the-mean perspective. I wonder how effective Roy Halladay would be as a closer? John Smoltz comes to mind.

The thing about Josh Johnson is that he's had a lot of short seasons due to injury. He's had 6 full seasons in the majors and pitched fewer than 90 innings in half of them. He's topped 160 innings only twice. That's how he made this list--by being a really good pitcher but rarely pitching something like a full season.

Incidentally, if we look just at starting pitchers in 2011, there are a handful to get 2.5 WAR per 100 innings pitched:

Rk		WAR	IP	Age	Tm	G	GS	ERA	ERA+
1	Doug Fister	5.7	216.1	27	TOT	32	31	2.83	139
2	Roy Halladay	7.4	233.2	34	PHI	32	32	2.35	164
3	Cole Hamels	5.4	216.0	27	PHI	32	31	2.79	138
4	Clayton Kershaw	6.9	233.1	23	LAD	33	33	2.28	163
5	Cliff Lee	6.8	232.2	32	PHI	32	32	2.40	161
6	Ricky Romero	5.9	225.0	26	TOR	32	32	2.92	146
7	CC Sabathia	6.9	237.1	30	NYY	33	33	3.00	147
8	Justin Verlander	8.6	251.0	28	DET	34	34	2.40	170
9	Jered Weaver	6.6	235.2	28	LAA	33	33	2.41	158

Provided by Baseball-Reference.com: View Play Index Tool Used
Generated 11/10/2011.

I think we'd agree that these 9 guys were among the 12 or so best starters in the game this past year. So I think the WAR/IP measure does a nice job--it just also suggests that a whole bunch of relievers were even more valuable--if only they could pitch that effectively as starters.