Masahiro Tanaka’s knuckle-curve might be a game changer

Last week, I wrote about Masahiro Tanaka’s experiments with the knuckle-curve. I established that Tanaka’s knuckle-curve is indeed a new addition to his arsenal; it differs from his old curveball in both movement and velocity. In case you need to refresh your memory, here’s the pitch in hot GIF action:

And another one, for good measure.

Now the question to answer is, what compelled Tanaka to add the pitch to his arsenal?

As a general point, the ability to throw more pitch types is always beneficial, as it only adds to the long list of things that batters have to keep in mind. This is doubly so for Tanaka, whose repertoire hitherto seems well-rounded at first but suffers from a stars-and-scrubs arrangement.

As I noted in last week’s piece, Tanaka really has only two above-average pitches, his splitter and his slider, while the effectiveness of the rest of his repertoire lags far behind. Tanaka recognizes this; it’s why he threw his two best pitches over 60 percent of the time in 2018.

However, one has to ask how much further Tanaka can take this strategy. The slider and splitter are both pitches which work best when they’re located outside of the strike zone. If opposing hitters know (as I imagine they do) that Tanaka is going to lean heavily on the two offerings, they might be inclined to adopt a passive approach, forcing Tanaka to attack the strike zone with his less effective pitches.

Of course, such a tactic is easier said than done, as Tanaka’s slider and splitter are extremely difficult to lay off of due to their sharp and deceptive movement. No pitcher can have top-notch stuff all of the time, though. The more splitters and sliders Tanaka throws, the more likely he is to hang one, and the more likely that hitters are able to anticipate such mistakes and pounce. Having an additional “out” pitch throws a curveball (quite literally) in the plans of opposing batters, thus benefiting Tanaka greatly.

Tanaka’s reliance on his two best offerings leaves him with an additional disadvantage - the lack of a plan B. Few pitchers look as bad on their “off” days as Tanaka, as he has little to work with if his splitter/slider combo isn’t working. Adding a new weapon to his arsenal may help the right-hander to slog through starts where he doesn’t have his command, which would do wonders for his consistency. Imagine Tanaka, but with less of his patented blow-ups and more competitive starts. Assuming that we still get our regular dose of vintage Tanaka Time in every other start, such a season would at least be worthy of some down-ballot Cy Young votes.

In addition to reducing Tanaka’s predictability and improving his consistency, his new knuckle-curve has benefits pertaining to the nature of the pitch itself. Its trajectory suggests that it would play very well off of his splitter - just not in the way you’d think.

When it’s working, Tanaka’s splitter is the cruelest pitch on the planet. Out of his hand, it looks like an 86 MPH meatball down in the zone, perfect for golfing out of the yard. Then, just as the batter starts to pull the trigger, it disappears like that flaky friend that promised he’d go to the party with you. The victim, left with nothing but a whiff, swears never again; a resolution that crumbles as soon as he faces Tanaka once more.

Throwing the split does come with its fair share of risk. This is what happens when Tanaka’s splitter does nothing, as he learned the hard way with his third MLB pitch:

Sometimes the flaky friend does show up, and he ends up being the life of the party. When Tanaka’s splitter doesn’t split, it behaves just like what it initially appears to be—an 86 MPH meatball. Combine that with bad location, and you have yourself an earned run.

Every hitter facing Tanaka has this in the back of their mind. It’s part of what makes Tanaka’s splitter such a difficult pitch to lay off of. Once a gambler gets a taste of the jackpot, the poor soul will never be able to resist betting large on small odds. Likewise, the potential reward of making contact with a hanging Tanaka splitter is what entices opposing batters to swing at the pitch, even if the numbers show it’s nearly impossible to hit when located properly and moving as designed. Yet this works both ways. Even though Tanaka is right to rely on his splitter because it’s a really good pitch, every time he throws it he’s risking a dinger.

With that in mind, let’s compare Tanaka’s hanging splitter to his new knuckle-curve. Is it just me, or do the two pitches look eerily similar, before the latter breaks and the former doesn’t?

Tanaka’s knuckle-curve looks just straight enough to seem like a hanging splitter at its start, but is slow enough (80 MPH) and has enough horizontal movement to miss overeager swings. On its own, the pitch doesn’t seem like anything special, but coupled with the specter of a hanging splitter, it has the potential to be quietly and devastatingly effective.

As Sun Tzu proclaimed in The Art of War, if you know yourself and know your enemy, you will not be imperiled in a hundred battles. Masahiro Tanaka is well aware of his strengths and weaknesses. He also knows how opposing batters seek to take advantage of his mistakes - by waiting on hanging splitters. Accordingly, Tanaka has adopted a new pitch seemingly designed precisely to upset batters’ expectations. With his new knuckle-curve, Tanaka might be ready to take his game to a new level.