Breaking down Masahiro Tanaka’s scoreless start

Masahiro Tanaka’s latest start against the Blue Jays was a marvel. It was the first time that a Yankees starter had thrown a scoreless start since July 12, when Domingo German blanked the Canadian bluebirds over six innings. With the starting rotation, Tanaka included, struggling mightily in the time since then, Tanaka’s start gave many Yankee fans a much-needed confidence boost.

However, it would be jumping the gun to declare Masahiro Tanaka all the way back after one start. Perhaps some of you may remember April 27 of 2017, when Tanaka overcame a horrendous start to the season to throw a complete-game shutout against the Boston Red Sox. Despite that dominant showing, Tanaka continued to struggle throughout the first half, only really regaining his form in the latter months of the season.

Is Tanaka’s most recent start just a random bounce back like that 2017 against the Red Sox? Or is it really the start of a return to form? There’s evidence for both sides, but ultimately it looks like Tanaka is still trying to work things out.

First, let’s look at the good parts. Tanaka’s slider has replaced his splitter as his best pitch in 2019, and it was on full display against the Blue Jays. Of the 94 pitches he threw that day, 33 were sliders, and 28 of them went for strikes. Here’s how he located his sliders that day.

Against lefties (catcher’s view):

FanGraphs.com

And against righties:

FanGraphs.com

Against lefties, Tanaka didn’t really locate his slider as well as we’d think, with a bit more misses in the high outside corner than you’d usually expect from a scoreless outing. However, he was able to get away with those misses due to the sharp break he had on the slider, inducing hitters to swing on top of such misses rather than squaring them up.

And as for the ones he located down and in? The Blue Jays had no chance.

Everybody talks about Tanaka’s splitter, but in reality he relies on his slider just as much. With his splitter inconsistent, Tanaka has to execute his slider to get people out. Luckily for him and for the Yankees, his slider has been causing him few problems throughout the year, and the Blue Jays felt the full wrath of it on Sunday.

However, it wasn’t all sunshine and flowers for Tanaka during his outing (although it is hard to glean truly bad details from such a stellar start). His splitter, while trending in the right direction, still was nowhere near as effective as usual. To wit: Tanaka threw 25 splitters, but none of them garnered any whiffs from the Toronto bats. The culprit was inconsistent location, as evidenced by these heatmaps.

Vs. LHB

FanGraphs.com

Vs. RHB

FanGraphs.com

When Tanaka is at his best, he can pepper the area below the zone with splitters, making hitters look silly trying to golf them. The trouble begins when Tanaka is unable to locate his splitters, leaving them high in the zone like he did against the Toronto lefties, or burying them too much as was the case against their righties.

Tanaka’s splitter needs to be located precisely in order to be effective. That kind of command was not present against the Blue Jays, and it showed in Tanaka’s low strikeout total (four). That issue needs to be rectified before we can start talking about how Tanaka got his groove back.

Tanaka is a great pitcher. He’s had an up-and-down season, but his track record suggests that he’ll lower his ERA from here on out. For that to happen, however, he needs to start locating his splitter. While his start against the Blue Jays was encouraging in other ways, it wasn’t on that front. All eyes are on Tanaka as he looks to right the ship.