Zach Britton might have a trick up his sleeve

The Yankees signed Zach Britton last weekend. The contract terms are, of course, a little complex, with Scott Boras negotiating what he has termed a “swellopt”. Britton will make $26 million over the first two years of his deal, after which the Yankees can either tack on a fourth guaranteed year worth $14 million, or simply let Britton play out his third contract year at $13 million. If the Yankees opt against the fourth year, Britton can decide whether to play out the third year or opt out for free agency.

The swellopt provides both some upside for the Yankees in case Britton is great and some security for Britton in case he struggles. In analyzing the move last Sunday, I didn’t spend much time on what Britton is actually due to be paid. Far more important, to me, is the quality of Britton’s play, both in the past and the future, and what that means for the Yankees.

Still, it could be argued that the Yankees have “overpaid”. Coming off an uneven season, Andrew Miller secured a two-year, $25 million pact. Coming off an excellent run of performance, David Robertson represented himself and signed for two years, $23 million. Britton garnered a much greater contract than each despite not having a stronger recent track record.

What makes the Yankees so confident Britton will live up to his previous form and hold up during the length of this contract? The Yankees could have myriad reasons to believe Britton will be excellent going forward. I outlined some of them at the end of the season. In reading around about the Britton deal, I stumbled on what could be another potential reason.

Jeff Sullivan wrote up the Britton signing for FanGraphs, and he too highlighted the mild discrepancy between Britton’s market and market for other relievers in his range. At the end of his analysis, he noted something interesting; Britton, a notorious sinkerballer, had toyed with what looked like a four-seam fastball a bit at the end of 2018. This was something I imagine hardly anyone noticed, but the mere fact that Britton and the Yankees have engaged in such tinkering suggests they have ideas to maximize Britton’s time in pinstripes.

Britton’s reliance on his sinker is well-documented, and well-reasoned; it’s probably the best sinker in the game, so why not ride it for what its worth? In 2017, Britton threw his sinker 95% of the time, per Brooks Baseball. In 2016, 92% of the time, and 90% in 2015. In each instance, when Britton didn’t throw the sinker, he went with his breaking pitch, never a four-seamer, or a changeup, or a cutter.

Yet a few times last year, Britton threw a four-seamer. What differentiates the four-seamer from the sinker is that the four-seamer doesn’t sink, obviously. A four-seamer “rises” when compared to a sinker, doesn’t have nearly as much horizontal movement, and typically flies a bit faster than a sinker.

Let’s go to the tape. According to Brooks Baseball, the last four pitches of Britton’s last outing of the regular season were four-seamers, all to Red Sox first baseman Steve Pearce. Here’s a look at the one he threw on 3-1:

That’s unmistakable. Identifying pitch type from center-field camera shots can be tricky, but this appears to be clear as day; Britton’s fastball does not sink, and instead rides to the upper-right-hand corner of the zone. It hardly has any arm-side run. That looks like a good, clean, straight 95 mph four-seam fastball.

Here’s a plot of Britton’s pitches that night, based on vertical movement and speed:

You can see the clear differentiation between the four-seamers and the sinkers. While Britton didn’t actually throw the four-seamer much harder than normal, it clearly had more ride. It’s interesting that Britton decided to throw four straight to a good hitter in Pearce in the bottom of the ninth in the game that eventually clinched home field for the Yankees in the Wild Card Game.

The first time Britton toyed with this fastball appears to be on August 5th, also in Boston. I couldn’t find footage, but he threw three straight four-seamers to Sandy Leon after falling behind 3-0, ultimately walking Leon. Again, Britton went to the four-seamer in a tight spot, behind in the count.

The only other time Britton was classified as having tossed multiple four-seamers was actually in the Yankees’ final game of the year, ALDS game four. With one out and none on, having just let in a run and facing Andrew Benintendi with a 1-0 count, Britton fired two consecutive four-seamers. Here’s the second one:

The location of this pitch makes it harder to see the four-seamer’s characteristics than it was with the one we saw earlier, but still, this pitch appears straight as an arrow. It does not drop the way Britton’s sinker drops. Down 2-0 to one of Boston’s best players, with the season on the line, Britton fired a four-seamer.

What this all indicates, in my eyes, is a willingness to get creative on both Britton and the Yankees’ part. Britton has always relied almost exclusively on his sinker, and it’s gotten him far, but some of his struggles early in 2018 showed that the sinker isn’t impenetrable. A riding four-seamer would give opposing hitters another look, something to keep in the back of their mind, something to keep them on their toes. The plots of Britton’s release point indicate that there was no discernible shift when Britton flitted between the two pitches, so hitters shouldn’t be able to detect which one is coming just off release point:

At certain times, all against the Red Sox coincidentally, Britton unveiled a new fastball. The pitch has promising attributes, and that Britton used it in surprisingly key spots shows he already may have some confidence in it. Perhaps it will become a vital part of his repertoire next year, or perhaps he’ll throw 95% sinkers again. Regardless, I think this shows the Yankees and Britton have plans to try and make the most of his time in the Bronx. If you thought Britton’s guarantee was a bit pricey, maybe the Yankees and their left-handed relief ace have some tricks up their sleeves to try and assuage your concerns.