Casey Janssen: “I’m a Strike Thrower”

Sort relievers backwards by velocity, and only four closers are in the bottom 30. Sergio Romo and Huston Street live on their sliders, Koji Uehara has his splitter, and then there’s Casey Janssen, humming along with his cutter and a 90 mph fastball. I asked him how he does it, and he graciously answered without resorting to fisticuffs.

Sort that same qualified reliever leaderboard, and you see that Janssen’s 4.3% walk rate this year is 11th-best in baseball. “I’m a strike thrower,” he says, “I have multiple pitches that I throw for strikes, and there’s some uncertainty in what I’m going to throw, keeping them off-balance.” Of course Janssen is right, take a look at the rate at which he gets balls with his main pitches with respect to the league rate:

Janssen Ball% League Ball%
Fastball 31.5% 41.2%
Curve 36.2% 40.9%
Cutter 34.0% 34.0%

Since Janssen’s primary outpitch is a curveball, he doesn’t have worry too much about lefties in particular — curves are among the most platoon-neutral pitches in baseball. And Janssen agrees, saying he doesn’t vary his approach much depending on handedness. If a lefty struggles with a slider, he may throw it, even if he doesn’t throw the pitch much. He promises he has a changeup, and he’d use it against the right hitter. But mostly, he’s “reading swings, reading hitters, reading weaknesses.” As he puts it, “honestly it’s just hitter to hitter,” and his usage reflects that. He uses his curveball about 4% less often against lefties, and otherwise his mix is largely the same.

In order to take the most advantage of his control, he wants to know about these tendencies. Janssen studies heat maps, scouting reports and video on hitters in order to be well versed in their strengths and weaknesses. “You try to be as prepared as you can,” he says, but admits that “sometimes your strengths are their strengths and you just say, ‘let’s go!'”

One remarkable aspect of Janssen’s game is that he’s improved on his control every year. His walk rate was never even league average, but over the last five years, he’s whittled that number down from 7.3% to 4.3%. How did he do that? “It sounds stupid but, if you can throw one pitch down and away, why can’t you do that all the time,” answers Janssen. He believes he’s “grown as a student of the game” and has learned his craft, but really it’s been about an effort to repeat his delivery, master down and away, and then let everything feed off of that.

Looks like he’s been successful in that regard. Look at a heat map for all of his pitches against right-handers in 2012:


Just because he throws strikes doesn’t mean there isn’t a cat-and-mouse game that comes of it. “Sometimes you can throw an intentional ball on purpose and there’s other times when you can force contact in certain counts so you don’t get to those damage counts where it swings to the advantage of the hitter,” Janssen says.

With a decent ground ball rate, Janssen has managed to avoid the homers when he does force contact, but it was the first part of the statement that got me interested. Are there times when you’d throw an intentional ball on the first pitch? Janssen agreed that this is a “Strike one league” but he said “certain guys are more ambush guys than others,” so you may want to entice those into swinging at a ball on the first pitch. Basically: “I’m a strike-thrower; Hitters know that, so sometimes you can use their aggressiveness against them.” That might be why Janssen, despite his great walk rate, is only 63rd among qualified reliever in first-strike rate. He has to ambush the ambushers.

Janssen used to have the best framer in the league behind the plate in Jose Molina, and he tried to break down what was so effective about Molina’s work: “he has little movement back there, and he’s a big guy, so maybe umpires don’t see the movement as much.” The Jays reliever also speculated about the work Molina did in conversation with the umpire (‘Hey I need that pitch’) since most catchers do that in some respect. But in the end Molina “has a gift, I don’t think everyone can do what he does.” When asked if it doesn’t matter, to some extent, what the catcher is doing if he can hit his spots, Janssen agreed, adding: “But then you get greedy and you start creeping more and seeing how much more you can get.”

And in fact, this might be the secret to Janssen’s approach. Once he’s gathered all his information about the hitters, and watched a few innings to get a sense of the umpires’ zone, and asked his catcher for any last minute quirks in the daily zone, it’s time to begin stretching the zone. “If you try and hit a spot, and if he doesn’t give it to you, you creep back to the plate, and then if he gives it to you, you go back the other way. If it works, it works, if not, you’ve got to get back on the plate,” describes Janssen. Not surprisingly, Janssen can hit the edge of the strike zone well, and this ability shows up well by Edge%, where his 19.4% since 2008 puts him near the 75th percentile in the statistic.

Casey Janssen is a strike thrower, and he doesn’t have a choice. “Because I’m not overpowering, I have to be more precise with my command,” he’ll readily admit. But there’s a lot behind each strike: years of practice repeating his delivery, hours of studying on the hitters, and then a minute-by-minute game to push the strike zone as far as it will go during that appearance.

Thanks to for some of the pitch selection numbers in this piece.

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With a phone full of pictures of pitchers' fingers, strange beers, and his two toddler sons, Eno Sarris can be found at the ballpark or a brewery most days. Read him here or at October. Follow him on Twitter @enosarris.

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He’s underappreciated around the league, I think. As is Brett Cecil.


Cecil may be the incumbant replacement

I think he closed in college


I hope the Blue Jays keep both.