Sinkers Aren’t Sunk:

Finding Value in Sinkerballers

By John White

The sinker has a bad reputation in fantasy baseball.  The common perception is that a sinkerball pitcher is a “pitch to contact” guy who will have too many balls put in play to be of much value on a fantasy baseball squad; he won’t generate elite strikeout numbers, and more balls in play will inevitably have a negative impact on WHIP, since this type of pitcher is more dependent on the defense behind him than his four-seam fastball pitcher counterparts.  Furthermore, the modern batter’s approach, emphasizing an uppercut swing to generate loft and try to launch dingers into the cheap seats, puts too many sinkers right into a batter’s wheelhouse, where it gets crushed. There is some validity to this. However, a deeper dive into pitchers who rely on sinking their fastballs allows a fantasy baseball manager to find real value for their squad, often at an Average Draft Position or Auction cost well below the return on the investment.

This list would have taken considerably longer to compile without the excellent spreadsheet put together by Alex Chamberlain and made readily available on his Twitter profile (@DolphHauldhagen).  Many thanks go to him.  If the conclusions that follow are faulty, blame my understanding of his work.

In order to set a baseline for effective sinkerball usage, I first set the spreadsheet to only look at sinker Pitch Type Outcomes in 2019.  Then, I selected noted sinker relief pitcher Blake Treinen, and looked at how many sinkers he threw in 2019 (an admittedly off year for his fantasy production).  Brooks Baseball credited Treinen with 442 sinkers in 2019, as did Chamberlain’s spreadsheet.  That became the minimum, in order to make the sample size large enough to be meaningful.  I set no upper limit in sinker usage. Next, I set a minimum of a 10% strikeout rate. Most fantasy baseball leagues these days incorporate some strikeout data in pitcher categories, so this minimum means that the pitchers sorted will provide some K value.  Lastly, I set a maximum BB% of 10% to increase the odds of selecting pitchers with positive fantasy value; sinker pitchers may rely more on batted ball outcomes more than others, but their tendency to issue free passes is almost entirely within their own control.  This produced 17 names, for a workable list. Amusingly, Treinen did not qualify for this list, despite setting the low-end baseline of sinkers thrown.

Chris Bassitt had the best xwOBAcon for his sinker of these seventeen pitchers, at .287.  His .440 FIP overall might look a little scary, but, as indicated earlier, sinkerball pitchers are somewhat more fielding dependent than their counterparts.  Note that Bassitt also benefits from the elite defense of both Matt Chapman at 3b, and Matt Olson at 1b, so the defense won’t be hurting his ERA or saddling him with too many unearned runs. With 141 strikeouts and a WHIP of 1.194, Bassitt is a reasonable contributor in traditional fantasy baseball categories on a  contending real-life team, with a bargain Steamer ADP of 240.

Steven Matz had the most impressive K% of this group, with 24% of his sinkers being whiffed at in 2019. His 153 strikeouts overall were certainly useful in traditional fantasy baseball categories, and while his 1.341 WHIP wasn’t elite, it wasn’t a category-killer either, and 160  innings are also useful in an environment where innings limits and weekly pitch minimums are considerations. As with Bassitt, Matz pitches on a team with reasonable playoff aspirations, so should provide double digit wins if he stays healthy. Currently, his Steamer ADP of 242 puts him just behind Bassitt. 

If you gravitate toward FIP as a predictive stat, Cubs’ reliever Brandon Kintzler might interest you, as his 3.57 FIP was the best of the bunch.  He worked 60 innings last season, picking up a Save, a few Holds, and 3 Wins with a WHIP of 1.018.  At a minimum, those numbers can provide some streaming value in deep or NL-only leagues, assuming his new coaching staff uses him similarly.  His composite ADP of 489 makes him essentially free to draft. 

Lastly, Joey Lucchesi threw the second-most sinkers of this bunch – 1341 of them in 2019.  His 163 innings pitched were themselves valuable, especially with 158 strikeouts in those innings.   The 1.222 WHIP might not be elite, but it won’t drag down the category, either. Expect those innings to come with double digit wins as his Padres look loaded for a playoff run.  His .297 BABIP on the sinker looks entirely repeatable, even high, with Machado and Tatis, Jr. behind him. Like Bassitt and Matz, his Steamer ADP of 235 makes him a viable SP4/5 target in most formats.