Repertoires in review: Who has the best sinker on the St. Louis Cardinals?

Back on December 21st (happy new year, by the way), I began with part one of a projected four-part series that I have conveniently titled "repertoires in review." The thought process behind the production of these pieces was to get a general feeling of the best individual pitches on the St. Louis Cardinals as we crawl closer to the 2016 season. According to the poll at the bottom of December's article, it is believed that closer Trevor Rosenthal possesses the staff's best fourseam fastball, as he captured 73% of the vote.

Frankly, this should not be seen as a shocking result, either, considering Rosenthal is an All-Star pitcher, and the fourseam fastball is a pitch he uses nearly 75% of the time. Now, I did read through the comments, and I do agree that Rosenthal, as a closer usually reserved for just one inning of work, has an unfair advantage over starting pitchers like Lance Lynn and Carlos Martinez. That being said, even if Rosenthal was in the rotation (as he was in the low minors and as I wished for nearly two years ago), I still believe he would have the staff's best fourseamer. Sure, the vote would be much closer, but in the end, he'd still likely come out on top.

Enough about fourseamers, though, this article is meant to be about sinkers, which, in my opinion, are significantly more interesting than fourseamers, and, in theory, should be impacted less by the type of pitcher (starter versus reliever). Even though Dave Duncan is no longer the pitching coach, inducing ground balls remains to be one of the main goals of the pitching staff (and as a whole, they did quite well at it in 2015), and it all starts with a consistently effective sinker. After looking at each pitcher's 2015 repertoire on BrooksBaseball.net, I settled on five pitchers (as seen in the table below) to consider for the "best sinker" on staff.

The basics (using 2015 PitchF/x data)

Honestly, there is not too much separation here as four of the five throw their sinker in the 90-92 MPH range. Maness is predictably at the bottom of the list in terms of velocity but finds his name at the top when it comes to frequency. Martinez may throw his sinker less frequently than any other pitcher included in the comparison, but his average velocity is roughly four to five MPH faster than the rest of his staff mates. Plus, according to this PitchF/x leaderboard on Baseball Prospectus, Martinez's sinker has the seventh fastest average velocity in all of baseball. While velocity is not the most important aspect to consider with a sinker, it is definitely helpful, especially if a pitcher is having trouble with location during an outing.

2015 movement

Remember: Regarding horizontal movement, a positive value means arm-side movement for left-handed pitchers, while a negative value means arm-side movement for right-handed pitchers.

For the sake of completeness (and the fact that this piece is on sinkers), I included dragless vertical movement + gravity in the table, but as with most of my PitchF/x posts, I tend to focus more on dragless horizontal movement. Why? To be frank, horizontal movement is what leads to broken bats, weak contact, and/or uninspiring swings—all three being primary goals of a pitcher. Garcia, Leake, and Lynn all have comparable horizontal movements, with Maness a half an inch or so ahead of them. Yet, once again, Martinez surfaces to the very top, just as he did with velocity.

2015 pertinent outcomes

Ground balls. Ground balls. Ground balls. When it comes to sinkers, it is clear that inducing ground balls is a priority. Garcia, Lynn, and Martinez each get ground balls on 64+% of sinkers put in play, but their rates are so close that you have to look elsewhere if you want to distinguish a noticeable difference. So, what happens when a hitter happens to lift the pitch into the air? How frequently does it leave the park? Or, does the pitcher enjoy success by inducing swings and misses as well? As with the first two categories, Martinez is the clear winner once again. He induces the most swings and misses, and hitters very rarely connect for a home run on his sinker. In fact, Martinez has thrown 1,186 sinkers in his career, and only one of them has resulted in a home run.

2015 results

Given that the pitch is at least partly reliant on batted ball luck, it is not all that surprising to see relatively high batting averages across the board. That being said, the pitch's efficacy is much better determined by looking at isolated power (ISO), as allowing a seeing-eye single to right field isn't nearly as big of a deal as a ripped double into the right field corner. Velocity and horizontal movement are both incredibly important when it comes to inducing weak contact, so it is predictable to see Martinez with the lowest ISO of the group.

Martinez strikeout of Chris Johnson on July 25th (BrooksBaseball)

BrooksBaseball has this sinker at a tick over 97 MPH, and as you can see from where Yadi original set his mitt, the sinker's horizontal movement is nothing short of extraordinary.

via The Pitcher List

Based on the data presented in the article, I think it is pretty clear who has the best sinker on staff, but let's confirm it by answering the poll question below. Feel free to voice your opinion in the comments section as well.