Verlander is Fourth Among Tigers All-Time Pitching Runs Leaders

In an earlier post, it was noted that ERA+ is a reasonable metric for measuring the quality of a pitcher's innings, but it does not address quantity.  For example, former Detroit hurlers Mickey Lolich and Dan Petry each had a Tigers career ERA+ of 105.  However, Lolich pitched almost twice as innings (3,361 versus 1,843) and ERA+ does not give him credit for his heavier workload.

The Pitching Runs statistic, introduced by Pete Palmer in The Hidden Game of Baseball in 1984, was designed to account for both the quality and quantity of a pitcher's work.  It tells us the number of runs saved or lost by a pitcher compared to league average.  It is based on a pitcher's innings pitched (IP), earned runs (ER) and the league average ERA (Lg ERA):

Pitching Runs = IP x Lg ERA/9 - ER

For example, Tigers current ace Justin Verlander had a 2.40 ERA in 251 IP in 2011.  Based on the league average ERA of 4.08, we can estimate that an average pitcher would have allowed 4.08 x 251/9 = 114 ER in 251 IP.  Verlander allowed 67 ER, so he had 114 - 67= 47 Pitching Runs.  Therefore, he saved the Tigers an estimated 47 runs compared to the average pitcher in the same number of innings. 

The calculation above is the basis of the Adjusted Pitching Runs (PtchR) measure found on Baseball-Reference.  Baseball-Reference makes adjustments for a pitcher's home park and pitcher/team earned run to run ratio.  Thus, a pitcher pitching in an offense-oriented park would have his Pitching Runs adjusted slightly upwards, whereas a pitcher pitching in a pitcher-friendly park would have his Pitching Runs lowered a little.  A pitcher, who allows more/fewer earned runs than his team ratio of earned runs to runs would suggest, also gets his Pitching Runs tweaked up/down.

The career Pitching Runs leader board for Tigers starters is shown in Table 1 below.  The top of the list looks similar to the ERA+ chart, but there is more spread due to innings pitched.  Prince Hal Newhouser edges out Tommy Bridges 277 to 275 and Dizzy Trout is a distant third at 204.  Verlander is still fourth as he was on ERA+, but it will take him a few seasons to catch the leaders.

Table 1: Tigers All-Time Pitching Runs Leaders, 1901-2011

Player	From	To	IP	ERA	ERA+	PtchR
Hal Newhouser	1939	1953	2,944	3.07	130	277
Tommy Bridges	1930	1946	2,826	3.57	126	275
Dizzy Trout	1939	1952	2,591	3.20	125	204
Justin Verlander	2005	2011	1,315	3.54	124	127
Frank Lary	1954	1964	2,008	3.46	116	114
Jack Morris	1977	1990	3,042	3.73	108	113
Jim Bunning	1955	1963	1,867	3.45	116	113
Schoolboy Rowe	1933	1942	1,445	4.01	114	99
Virgil Trucks	1941	1956	1,800	3.50	114	98
Bobo Newsom	1939	1941	760	3.59	132	90
Fred Hutchinson	1939	1953	1,464	3.73	113	83
Mickey Lolich	1963	1975	3,361	3.45	105	80
Dave Rozema	1977	1984	1,007	3.38	120	69
Bill Donovan	1903	1918	2,137	2.49	109	67
Denny McLain	1963	1970	1,593	3.13	110	66

 Data source: Baseball-Reference.com

Jack Morris was only 13th on the ERA+ list, but his 3,042 innings propels him to 6th in Pitching Runs.  Similarly, Lolich rises from 15th to 12th.  Other pitchers such as Ed Killian and Dan Petry made the ERA+ top 15 but do not appear on this list due to lighter workloads.

There was one pitcher with only 760 innings who did make the Pitching Runs cut.  That was the eccentric Bobo Newsom who pitched for the Tigers from 1939-1941 and was one of the stars of the 1940 pennant winner.  His 132 ERA+ would have topped the ERA+ list if he had enough innings to qualify.  The well-traveled right hander pitched for nine major league teams, but had his best years for the Tigers.