Bartolo Colon Strikes Them Out Looking
Last night Bartolo Colon threw a clunker fo the New York Yankees against the Tampa Bay Rays. But, what makes that clunker so amazing is that after twelve starts for the Yankees this was just the third bad start for Colon. After not pitching in 2010 and with just limited success since 2005, Colon's 2011 has been a major surprise. He is striking out 7.9 batters per nine innings, the best since 2001, while maintaining his great command.
Colon is getting the majority of these strikeouts on called strikes. Typically high-strikeout guys get lots of swinging strikes, and Jeff Sullivan showed that swinging-strike rate correlates very well with strikeout rate. But Colon is in the bottom ten among starters at getting swinging strikes, but is solidly above average at getting strikeouts. Jeff Sullivan actually wrote about this strange fact back in May. Colon's strikeouts are coming overwhelmingly on called strikes. He has the highest rate of called strikes (called strikes per pitches) among pitchers with over 500 pitches at 23.7%. The major league average is 17.5%, the next highest is Carlos Marmol with 23.1% and the next starting pitcher is Kyle Lohse with 21.9%.
Colon throws almost all fastballs, 84%. That makes the called strikes that much more interesting. Batters almost surely know that a fastball is coming, but Colon gets takes in the zone anyway. A big part of this comes down to location. Here are the locations of his two- and four-seam fastballs in 2011, with called strikes circled.
Here are three possible — though non-exhaustive and nonexclusive — explanations for his called strikes: (a) Colon hits the corners better than other pitchers; (b) hitters take his pitches in the zone more often than against other pitchers; and (c) umpires call his taken pitches on the edges more often than other pitchers.
Looking at (a):
Turing to (b), here I just look at pitches that are vertically in the zone (between sz_top and sz_bot):
Finally looking at (c), again these are pitches within the zone vertically:
Overall Colon benefits from all three possible factors: he throws more pitches on the edge of the zone than the average pitcher; his inside two-seam fastball is taken at a very high rate; and his taken pitches are more likely to be called strikes. His last start not withstanding, I am not sure whether he can keep this up. Maybe the league will get on to him and start swinging at his pitches more often. Historically it has been very hard to keep a strikeout rate that high missing so few bats.