Innings Per Start: Pedro/Schilling

In comments to my Pedro post, Jack said "the inability [of Pedro] to finish games has to be factored in" when discussing his all-time greatness. Part of that way of thinking is that the longer an ace starter lasts, the more he prevents a lesser arm from coming into the game. He mentioned Curt Schilling, Roger Clemens and Sandy Koufax as more durable pitchers.

Baseball is not played the same way in 2006 as it was in the 1960s and the lack of complete games should not be held against Pedro. Even if Martinez could go nine innings every time out, no manager or front office would allow it.

Here are the starts, innings pitched, average innings per start and ERA+ for Martinez and Schiling. Pedro's stats are his entire Red Sox career (1998-2004) and the 2005 season with the Mets. Curt's stats are with Philadelphia (1993-2000), Arizona (2000-2003) and Boston (2004).

            Martinez              Schilling
Age GS   IP    AVG  ERA+  GS   IP    AVG   ERA+
26  33  233.2 7.07  160   34  235.1  6.92  100
27  29  213.1 7.35  245   13   82.1  6.33   96
28  29  217.0 7.48  285   17  116.0  6.82  121
29  18  116.2 6.47  189   26  183.1  7.05  138
30  30  199.1 6.64  196   35  254.1  7.26  143
31  29  186.2 6.43  212   35  268.2  7.67  134
32  33  217.0 6.57  125   24  180.1  7.51  130
33  31  217.0 7.00  148   29  210.1  7.25  124
34                        35  256.2  7.33  154
35                        35  259.1  7.40  136
36                        24  168    7.00  159
37                        32  226.1  7.07  150

In their respective age 26, 27 and 28 seasons, Martinez averaged more innings per start than Schilling. Since then, Pedro has pitched fewer innings per start.

But it doesn't seem like that big a difference. At age 31 and 32, Schilling averaged almost 1.1 more innings per start. That sounds significant -- is it? -- but how many hits and runs did Schilling allow (if any) while recording those additional four outs. Relying only on innings pitched doesn't tell us what we want to know. And assuming effectiveness from those totals would be a mistake.

For example, what if Pedro pitched 6 shutout innings and Schilling allowed 4 runs in 7 innings? Schilling pitched deeper into in the game, but was not as effective. Judging by their respective ERA+s, something similar to this example must have happened more than a few times.

Schilling's best ERA+ seasons (2003 and 2001) are superior only than Pedro's final year in Boston (2004) when he turned in an un-Pedro 3.90 ERA. In every other one of his Boston seasons (save perhaps the first, 1998), his performance has dwarfed the career bests of Schilling.

That doesn't mean Schilling isn't a damn good pitcher (his outings in June, mostly against other top pitchers, were superb), but it makes me question whether not sticking around for those extra outs (in their age 33 seasons, the average is less than one out per start) should be considered a strike against Martinez.