Number 1 and Number 2 in the majors in pitches thrown during each regular season, 2009-2013:
2013 Justin Verlander 3,692, James Shields 3,657
2012 Justin Verlander 3,768, James Shields 3,617
2011 Justin Verlander 3,941, Dan Haren 3,774
2010 Dan Haren 3,749, Justin Verlander 3,745
2009 Justin Verlander 3,937, Felix Hernandez 3,633
Most regular season pitches thrown over the five years combined, 2009 through 2013:
1. Justin Verlander 19,083
2. Felix Hernandez 17,565
3. James Shields 17,529
4. C.C. Sabathia 17,138
5. Tim Lincecum 17,059
The size of the gap in pitches thrown between Verlander and Felix, #1 and #2 on the list above, is about 1,500 pitches. To find that size gap between Felix and a pitcher below him on this list, you would have to go down to #17 on the list.