Are relief pitchers becoming too dominant? Mike Marshall 1974: 208 innings, 106 games, all in relief.

It seems like every pitcher who comes out of the bullpen averages more than one strike out per inning.  Actually it's only about half the relief pitchers.  Below are numbers for every ten years going back 50 years.  1994 was a short season, so 1993 was used.

With 2014 almost complete, it appears that 2014 will be the only season examined in which no pitcher will reach 100 innings with zero starts; Dellin Betances leads with 85.  Queries were run in baseball-reference.com for IP>=50 and GS=0), sorted by greatest Strikeouts per 9 IP (SO9).

Willie Hernandez in 1984 won both the Cy Young and MVP awards; 140 innings in 80 games; but he averaged only 7.18 SO9.  Dick Radatz in 1964: 157 innings, 79 games, 10.38 SO9; Radatz was known as the monster.

Mike Marshall in 1974 won the Cy Young award: 208 innings in 106 relief appearances, SO9 6.18.   Part of what probably helped Marshall was that his pitch count might have been low because he had low strike out (143), walk (56) and hit (191) totals, relative to his 206 innings.  Those three things tend to increase pitch counts.  But modern pitching in 106 games, even if it had been only one inning per game, is still amazing.  Marshall averaged almost two innings per game.  All in relief, Marshall exceeded 100 innings in 1971, 1972, 1973 (179), 1974 (206), 1975, 1979 (142); 99 innings in 1976 and 1978.  Marshall's best SO9: 7.4 in 1972; his next best: 6.9 in 1971.  Marshall did not dominate.

For some perspective: Mariano Rivera pitched 1995-2013.  Rivera threw 100 innings only once: 107 in 1996 when he was the setup man for John Wetteland.  That was also Rivera's best SO9: 10.6.  Rivera had SO9 better than 9 in only 6 of his 18 full seasons; low: 1998: SO9 5.3 in 61 innings.  Rivera's second most innings: 80 in 2001: SO9 9.3.  Rivera was under 70 innings in 8 of 18 seasons.  Rivera might be obsolete one year after retiring.

year	tot	SO/9 > 9	pct	high	low	high	low	teams	>=100 Inn	SO/9 > 9 / teams
2014	111	53	47.75%	14.67	4.37	Andrew Miller	Dan Otero	30	0	1.77
2004	114	22	19.30%	14.93	3.3	Brad Lidge	Danny Kolb	30	1	0.73
1993	89	16	17.98%	12.18	3.38	Duane Ward	Steve Howe	28	4	0.57
1984	62	1	1.61%	10.21	2.85	Mark Clear	Dan Quisenberry	26	14	0.04
1974	38	0	0.00%	8.35	3.34	Al Hrabosky	Tom Burgmeier	24	13	0.00
1964	35	3	8.57%	10.38	4.09	Dick Radatz	Bob Duliba	20	7	0.15

The number of dedicated relief pitchers in 2014 and 2004 is about the same but the percentage with SO9 >= 9 jumped from 19.30% to 47.75%.  About half the relief pitchers in 2014 are doing what only about 20 percent did just ten years ago: blow the hitters away.  In 1984, 1974 and 1964 only a very few elite relievers did that.

Pitchers who did not start a game but threw at least 100 innings:

Rk	Player	SO9	IP ▾	GS	Year	Age	Tm	Lg	G	W	L	W-L%	SV	ERA	FIP	ERA+	HR9	H9	BB9	SO/W	WHIP
1	Scot Shields	9.31	105.1	0	2004	28	ANA	AL	60	8	2	.800	4	3.33	2.94	134	0.51	8.29	3.42	2.73	1.301

Rk	Player	SO9	IP ▾	GS	Year	Age	Tm	Lg	G	W	L	W-L%	SV	ERA	FIP	ERA+	HR9	H9	BB9	SO/W	WHIP
1	Greg Harris	8.25	112.1	0	1993	37	BOS	AL	80	6	7	.462	8	3.77	3.83	124	0.56	7.61	4.81	1.72	1.380
2	Jeremy Hernandez	5.64	111.2	0	1993	26	TOT	ML	70	6	7	.462	8	3.63	4.28	119	1.13	9.35	2.74	2.06	1.343
3	Joe Boever	5.54	102.1	0	1993	32	TOT	AL	61	6	3	.667	3	3.61	4.31	115	0.79	8.88	3.87	1.43	1.417
4	Alan Mills	6.10	100.1	0	1993	26	BAL	AL	45	5	4	.556	4	3.23	5.09	139	1.26	7.18	4.57	1.33	1.306

Rk	Player	SO9	IP ▾	GS	Year	Age	Tm	Lg	G	W	L	W-L%	SV	ERA	FIP	ERA+	HR9	H9	BB9	SO/W	WHIP
1	Willie Hernandez	7.18	140.1	0	1984	29	DET	AL	80	9	3	.750	32	1.92	2.58	204	0.38	6.16	2.31	3.11	0.941
2	Aurelio Lopez	6.15	137.2	0	1984	35	DET	AL	71	10	1	.909	14	2.94	4.09	134	1.05	7.13	3.40	1.81	1.169
3	Dan Quisenberry	2.85	129.1	0	1984	31	KCR	AL	72	6	3	.667	44	2.64	3.42	152	0.70	8.42	0.84	3.42	1.028
4	Bruce Sutter	5.65	122.2	0	1984	31	STL	NL	71	5	7	.417	45	1.54	3.05	227	0.66	8.00	1.69	3.35	1.076
5	Ted Power	6.71	108.2	0	1984	29	CIN	NL	78	9	7	.563	11	2.82	3.03	134	0.33	7.70	3.81	1.76	1.279
6	George Frazier	6.83	108.0	0	1984	29	TOT	ML	59	9	5	.643	4	3.92	3.23	102	0.58	8.17	3.33	2.05	1.278
7	Bob Stanley	4.39	106.2	0	1984	29	BOS	AL	57	9	10	.474	22	3.54	3.59	118	0.76	9.53	1.94	2.26	1.275
8	Gene Garber	4.67	106.0	0	1984	36	ATL	NL	62	3	6	.333	11	3.06	3.32	126	0.59	8.75	2.04	2.29	1.198
9	Craig Lefferts	4.77	105.2	0	1984	26	SDP	NL	62	3	4	.429	10	2.13	2.91	169	0.34	7.50	2.04	2.33	1.060
10	Keith Atherton	5.02	104.0	0	1984	25	OAK	AL	57	7	6	.538	2	4.33	4.46	86	1.13	9.52	3.38	1.49	1.433
11	Rich Gossage	7.39	102.1	0	1984	32	SDP	NL	62	10	6	.625	25	2.90	2.97	124	0.53	6.60	3.17	2.33	1.085
12	Lee Smith	7.66	101.0	0	1984	26	CHC	NL	69	9	7	.563	33	3.65	2.88	107	0.53	8.73	3.12	2.46	1.317
13	Gary Lavelle	6.33	101.0	0	1984	35	SFG	NL	77	5	4	.556	12	2.76	3.28	128	0.45	8.20	3.74	1.69	1.327
14	Ernie Camacho	4.32	100.0	0	1984	29	CLE	AL	69	5	9	.357	23	2.43	3.73	170	0.54	7.47	3.33	1.30	1.200

Rk	Player	SO9	IP ▾	GS	Year	Age	Tm	Lg	G	W	L	W-L%	SV	ERA	FIP	ERA+	HR9	H9	BB9	SO/W	WHIP
1	Mike Marshall	6.18	208.1	0	1974	31	LAD	NL	106	15	12	.556	21	2.42	2.59	141	0.39	8.25	2.42	2.55	1.186
2	John Hiller	8.04	150.0	0	1974	31	DET	AL	59	17	14	.548	13	2.64	2.96	143	0.60	7.62	3.72	2.16	1.260
3	Steve Foucault	6.61	144.1	0	1974	24	TEX	AL	69	8	9	.471	12	2.24	2.77	159	0.50	7.67	2.49	2.65	1.129
4	Pedro Borbon	3.43	139.0	0	1974	27	CIN	NL	73	10	7	.588	14	3.24	3.62	108	0.71	8.61	2.07	1.66	1.187
5	Tom Murphy	3.44	123.0	0	1974	28	MIL	AL	70	10	10	.500	20	1.90	3.74	189	0.44	7.10	3.73	0.92	1.203
6	Bill Campbell	6.66	120.1	0	1974	25	MIN	AL	63	8	7	.533	19	2.62	2.95	145	0.30	8.15	4.11	1.62	1.363
7	Rollie Fingers	7.18	119.0	0	1974	27	OAK	AL	76	9	5	.643	18	2.65	2.28	126	0.38	7.87	2.19	3.28	1.118
8	Sparky Lyle	7.03	114.0	0	1974	29	NYY	AL	66	9	3	.750	15	1.66	2.86	215	0.47	7.34	3.39	2.07	1.193
9	Diego Segui	6.33	108.0	0	1974	36	BOS	AL	58	6	8	.429	10	4.00	3.64	97	0.75	8.83	4.08	1.55	1.435
10	Chuck Taylor	3.59	107.2	0	1974	32	MON	NL	61	6	2	.750	11	2.17	3.53	178	0.67	8.44	2.09	1.72	1.170
11	Ken Forsch	4.18	103.1	0	1974	27	HOU	NL	70	8	7	.533	10	2.79	3.22	124	0.26	8.54	3.22	1.30	1.306
12	Tom House	5.61	102.2	0	1974	27	ATL	NL	56	6	2	.750	11	1.93	2.84	196	0.44	6.49	2.37	2.37	0.984
13	Elias Sosa	4.28	101.0	0	1974	24	SFG	NL	68	9	7	.563	6	3.48	4.02	110	0.71	8.38	4.01	1.07	1.376

Rk	Player	SO9	IP ▾	GS	Year	Age	Tm	Lg	G	W	L	W-L%	SV	ERA	FIP	ERA+	HR9	H9	BB9	SO/W	WHIP
1	Dick Radatz	10.38	157.0	0	1964	27	BOS	AL	79	16	9	.640	29	2.29	2.62	170	0.75	5.90	3.32	3.12	1.025
2	Hoyt Wilhelm	6.51	131.1	0	1964	41	CHW	AL	73	12	9	.571	27	1.99	2.58	174	0.48	6.44	2.06	3.17	0.944
3	John Wyatt	5.20	128.0	0	1964	29	KCA	AL	81	9	8	.529	20	3.59	5.03	107	1.62	7.80	3.66	1.42	1.273
4	Ron Perranoski	5.67	125.1	0	1964	28	LAD	NL	72	5	7	.417	14	3.09	2.99	105	0.36	9.19	3.30	1.72	1.388
5	Jack Baldschun	7.30	118.1	0	1964	27	PHI	NL	71	6	9	.400	21	3.12	2.95	112	0.61	8.44	3.04	2.40	1.276
6	Wes Stock	9.11	113.2	0	1964	30	TOT	AL	64	8	3	.727	5	2.30	3.51	167	1.19	6.81	3.33	2.74	1.126
7	Don McMahon	8.20	101.0	0	1964	34	CLE	AL	70	6	4	.600	16	2.41	3.29	151	0.62	5.97	4.63	1.77	1.178