Check out some of Ryan Vogelsong’s stats in 2011 and 2012:
Stat 2011 2012 G 30 30 IP 179.2 184.2 H 164 169 HR 15 17 BB 61 61 SO 139 151 WHIP 1.25 1.24
The numbers above are, for all intents and purposes, identical. But there’s one big difference: in 2011, he allowed 54 earned runs, whereas in 2012 he’s allowed 71. Those translate into seasonal ERAs of 2.71 (2011) and 3.46 (2012), and ERA+s of 129 in 2011 and 101 in 2012.
Why has a guy who has seemingly performed exactly the same on the mound allowed such different amounts of earned runs?
Let’s dig in to find out…
A big part of it is how Vogelsong has performed with runners in scoring position. With RISP in 2011, he allowed a slash line of .200/.320/.290 and 7 extra-base hits in 179 plate appearances. With RISP in 2012, he’s allowed a slash line of .222/.335/.333 and 12 extra-base hits in 190 plate appearances. The extra hits, pretty much all of the extra-base variety, led to 6 more earned runs so far in 2012.
It turns out that Vogelsong’s pitching with the bases empty is also worse in 2012. His BA allowed and OBP allowed are virtually identical between 2011 and 2012, but his SLG allowed is up from .368 to .400, over more than 400 plate appearances in each season. His total number of extra-base hits allowed in 2011 was 28 in 435 PAs, whereas in 2012 it’s been 38 in 454 plate appearances.
Allowed so many more guys extra bases means fewer double-play opportunities and more runners in scoring position.
Overall, Vogelsong is allowing fewer singles and more extra-base hits, and that’s been the difference in his runs allowed total.