Clayton Kershaw's Pretty Good At That Pitching Thing

He's one of only two 21-year-old pitchers to ever have a season with:

• ERA+: 146 or better
• ERA: 2.85 or better
• K: 171 or more
• H/9 IP: 6.3 or less hits allowed per 9 innnings
  

Not that ERA and ERA+ are the best statistical measurements of pitching, but Baseball-Reference's Play Index doesn't allow me to look up xFIP or FIP in historical comparisons.

I'd name the other 21-year-old, but I don't have a subscription to Baseball-Reference.

Looking at those numbers in the context that the vast majority of 21-year-old pitchers are either in college or in the minors, Kershaw's season is all the more impressive.