Since 1980, a pitcher under the age of 25 has recorded a sub-3.00 ERA over 162 or more innings 29 times. Of those 29 occurrences, 15 have been accompanied by strikeout rates of better than 7 per 9 innings. Here is a complete list of those, ranked in descending order by SO/9:

Player         Yr Age  IP    ERA  SO/9
Gooden,Dw      84  20 218   2.60 11.39
Perez,Ol       04  23 196   2.98 10.97
Prior,Ma       03  23 211.1 2.43 10.43
Fernandez,Si   85  23 170.1 2.80  9.51
Peavy,Ja       04  23 166.1 2.27  9.36
Rijo,Jo        88  23 162   2.39  8.89
Gooden,Dw      85  21 276.2 1.53  8.72
Webb,Br        03  24 180.2 2.84  8.57
Martinez,Ra    90  22 234.1 2.92  8.56
Clemens,Ro     86  24 254   2.48  8.43
Valenzuela,Fe  81  21 192.1 2.48  8.42
Zambrano,Ca    04  23 209.2 2.75  8.07
Smoltz,Jo      89  22 208   2.94  7.27
Gooden,Dw      86  22 250   2.84  7.20
Zito,Ba        02  24 229.1 2.75  7.14

Things to note:

• Six of these 15 performances came in the past three seasons.
• The only guy with an ERA lower than Jake Peavy’s is Dwight Gooden, who also is the only guy who shows up more than once in this list.
• Peavy is in real good company. Clemens and Smoltz are headed to the HOF, and the rest of these guys were some of the better pitchers of their era. Check out the career ERA+ of the pitchers who have worked more than 1000 innings: 141, 125, 120, 110, 110, 105, 103. (Peavy checks in at 112, right between Rijo and Gooden/Fernandez. Incidentally, Smoltz is #7 on Peavy’s list of similar pitchers through age 23.)

What did these guys do for an encore?

              IP         ERA+        SO/9
          Yr1    Yr2   Yr1  Yr2   Yr1    Yr2
Gooden84  218   276.2  137  226  11.39  8.72
Prior     211.1 118.2  175  113  10.43 10.54
Fernandz  170.1 204.1  123  100   9.51  8.81
Rijo      162   111    150  127   8.89  6.97
Gooden85  276.2 250    226  124   8.72  7.20
Webb      180.2 208    165  124   8.57  7.10
Martinez  234.1 220.1  126  111   8.56  6.13
Clemens   254   281.2  169  154   8.43  8.18
Valenzla  192.1 285    134  121   8.42  6.28
Smoltz    208   231.1  124  104   7.27  6.61
Gooden86  250   179.2  124  119   7.20  7.41
Zito      229.1 231.2  169  129   7.14  5.67

Prior and Rijo saw a severe dropoff in innings. Gooden saw a heavy increase, a slight decrease, then a heavy decrease. You think maybe nearly 750 big-league innings by age 22 wasn’t such a great idea?

Gooden saw his ERA+ improve dramatically from 1984 to 1985. All other encore seasons resulted in a worse ERA+.

Only Prior and Gooden (1986 to 1987) improved their strikeout rates, and only by a little in each case. Both also experienced a severe dropoff in innings to go with the improved SO/9. Some of these guys, notably the Dodger pitchers and Gooden (1984 to 1985), saw their strikeout rates fall off a cliff. Sadly, all three were barely hanging on by the time they reached their late-20s.

What can we learn about Peavy from all this? Every case is different obviously, and we’re just doing a quick-and-dirty examination here, but it seems pretty likely to me that his ERA+ and SO/9 will slip a bit in 2005. I guess that’s not exactly shocking; on the other hand, it’s always nice to have our suspicions validated in some way.

Assuming offensive levels stay about the same, Peavy’s worst case ERA is about 4.00 or so. I’ve seen the reports that suggest Peavy was lucky last year, but I’ll set the over-under for 2005 at 2.70. It’s aggressive, but I don’t think he’ll slip as far as some folks might expect.