From 2009 to 2012, Justin Verlander was unable to be touched. He was just a dominant pitcher that could retire hitters on a 100+ MPH fastball, or a selection of breaking pitches. He had 78 wins over that four year span, and a 2.97 ERA over that stretch. Then, the 2013 season came along. Verlander was picked in many first rounds of many fantasy drafts (he was in mine), and ready to build on a great 2012 season alone (17-8, 2.64 ERA). But then the unimaginable happened. Justin Verlander forgot how to pitch well.
This season, Justin Verlander is 12-10 with a 3.73 ERA. His K/9 (8.5), BB/9 (3.3), K/BB (2.6), HR/9 (0.9), BAA (.255), WHIP (1.36), and BABIP (.314) are all significantly worse than they were in 2009-2012. The oddest numbers of all these is his K/BB ratio. Let's compare his K/BB ratio from 2009 to 2013.
2009 -- 4.3 K/BB
2010 -- 3.1 K/BB
2011 -- 4.4 K/BB
2012 -- 4.0 K/BB
2013 -- 2.6 K/BB
As you can see, his ratio in 2013 is much lower than any of the four years prior to 2013. Analytically, this means that Verlander has lost his control, walking more hitters per every strikeout. This is an issue to say the least, as Verlander is putting more hitters on base via the free pass than ever before. Obviously, the more batters that reach base, the more likely the other team will score. So, this is a problem for Verlander, and needs to be fixed.
Another difference between Verlander's "prime" and this season is that Verlander has only thrown 17 two seam fastballs this season (0.56% of all pitches). In 2012, Verlander threw 226 two seam fastballs (6.01% of all pitches). His two seam fastball is a great pitch, as he has not allowed a hit off his two seamer this year, and had allowed a minimal .238 average off them last year. By not throwing two-seamers, it makes Verlander all that more predictable, which is ultimatley a lot more hittable.
Although his fastball's average velocity is at 94 MPH, which is low for Verlander (normally around 95 or 96), I don't think that is Justin Verlander's problem for being ineffective. Verlander needs to mix his pitches better, something he's had trouble doing this year.
I don't really know what is Justin Verlander's problem this year, but I have noticed a difference in the number of pitches he throws than normal, which is a sign that something is changed. But, for the Tigers, if Verlander can turn it around, they may be able to make a long run into the post-season. But, he needs to turn it around. I think Verlander is the Tigers x-factor of the season.