As Jose Fernandez Heads Off Into the Sunset

1. He finishes the season with a 2.19 ERA. In baseball history, there have been 13 seasons in which a pitcher 21 or younger has had an ERA below 2.25. Ten of those were in the deadball era. Since 1917, the only pitchers to accomplish this were Vida Blue (1971), Dwight Gooden (1985) and Fernandez.
2. The deadball era is a tough comparison because it was dominated by pitching. The only pitchers 21 or younger with a park-adjusted ERA 75% or more better than the league average (via Baseball-Reference's ERA+) are Blue, Gooden, and Fernandez.
3. He struck out 9.7 batters per 9 innings, making him the tenth pitcher 21 or younger to do so. The other nine are Sam McDowell, Dave Boswell, Tom Griffin, Frank Tanana, Dennis Eckersley, Gooden, Kerry Wood, Rick Ankiel, and Clayton Kershaw. Yow, that's a depressing group. Yes, Eck's in the Hall, but the only one on that list who qualified for the ERA title past age 31 was Tanana. Most were pretty much done before they were 30.
4. His strikeout-to-walk ratio was 3.22. He's the 12th pitcher 21 or younger to do that. The other 11 include several flameouts (Gary Nolan, Blue, Gooden) but also a couple Hall of Famers (Don Sutton, Bert Blyeven).
5. Here's the killer: Fernandez allowed 5.8 hits per nine innings. Nobody 21 or younger has ever done that. The closest anyone's come is Blue, 6.0 in 1971.

Conclusion: Fernandez had a historically great season. The track record of the peer group, though, should make us all cautious about projecting his (or, for that matter, Kershaw's) ability to keep it going.