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.

Print This Post

Graphs: Baseball, Roto, Beer, brats (OK, no graphs for that...yet), repeat. Follow him on Twitter @enosarris.

20 Responses to “Casey Janssen: “I’m a Strike Thrower””

You can follow any responses to this entry through the RSS 2.0 feed.
  1. Radivel says:

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

    +7 Vote -1 Vote +1

  2. Ty says:

    Watching Janssen on a regular basis, this year in particular he’s seemed to have a knack for getting called strikes right on the edge of the zone. If I was just watching him for the first time I’d consider many of these calls to be questionable or generous on the part of the umpire, but he does it remarkably consistently. So it’s really interesting to see what he has to say in the last few paragraphs about actively pushing to the edge of the strike zone, and then sitting right where he knows he’ll get calls.

    I’d imagine it takes an incredible amount of control to incrementally move the ball further and further outside until you hit that magic spot, let alone keep hitting it once you’ve found it. But that really does seem to be what he’s been doing this year, which is pretty impressive. Really interesting to hear that it’s an actual strategy on his part and not just good fortune.

    Vote -1 Vote +1

    • Mark says:

      That’s one of my favourite things to watch when Janssen is pitching. When he’s on, everything is right on the the outer limits of the strike zone.

      Vote -1 Vote +1

      • tbjfan says:

        Is it just me or does Casey Jansen throw a ‘flat’ fastball?

        The side-to-side movement looks very much non-existant; the trajectory looks like a straight line.

        I would imagine these type of pitches are really easy to catch, and really easy to frame for the umpires.

        I know that’s just my eye and it’s not super accurate or anything, but is there some truth to what I’m seeing?

        Vote -1 Vote +1

  3. Bubba says:

    Great article, love write-ups like these.

    Vote -1 Vote +1

  4. Mike Green says:

    Excellent piece.

    Vote -1 Vote +1

  5. marlins12 says:

    Would this type of thing show up in Edge%?

    Vote -1 Vote +1

  6. Sivart says:

    Having watched him his whole career, I’m a fan of Janssen, and think he’s a class act.

    Also, I like reading these pieces that get views from bright, humble, players that can offer some realistic (and non-cliché) insight into what they do.

    Vote -1 Vote +1

  7. Stieb's Moustache says:

    Great stuff – thanks. It’s a pleasure watching Casey pitch, and just about as stress-free a 9th-inning experience as you could ask for.

    Vote -1 Vote +1

  8. chief00 says:

    I can’t remember seeing a pitcher–whether a SP or RP–pound both sides of the bottom half of the strike zone with such consistency as he does. He’s a smart pitcher who gets the most out of his ability.

    Good article. It does him justice.

    Vote -1 Vote +1

  9. Kimbal Binder says:

    An artist at work…you have to admire Janssen for being smart enough and dedicated enough to develop his craft. Too many guys think it is about stuff, and not enough pitchers are willing to be so studious. Sure, I love Aroldis Chapman and his 101 MPH fastball. Imagine if Chapman began to be a thinking man’s pitcher? But I suppose it is the guys who need to be smart to stay in the bigs who figure these little things out, like “ambushing” first-strike hitters and adjusting to the strike zone of the day. Great article, Eno!

    Vote -1 Vote +1

  10. Jaker says:

    I <3 Janssen.

    Truly an artist.

    Vote -1 Vote +1

  11. The Nemesis says:

    After years of having the likes of Miguel Batista, Kevin Gregg, Frankie Francisco and other heart-attack-waiting-to-happen relievers coming in for the 9th, it’s nice to have a guy like Janssen who you just stick on the mound and let go to work.

    I just wish John Gibbons would be more willing to use Janssen in non-save situations when the need arises.

    Vote -1 Vote +1

    • Bob says:

      Remember Janssen had shoulder issues this spring and in the past. I think it’s more about Gibbons just being careful with Janssen. He’s used him in the bottom of the 9th in tie games this season as he should.

      Vote -1 Vote +1

  12. dc says:

    he’s underrated. period.

    this post was excellent. just missing the gif of the At bat vs davis the other day.. Davis is having an unbelievable start, Casey’s curveball embarrassed him twice in a row. it was a thing of beauty, it was literally like he had no chance.

    Vote -1 Vote +1

  13. everdiso says:

    Great article.

    As a bit of a skeptic when it comes to catcher “pitch-framing” stats, though, I thought it was interesting that you brought up Jose “super-framer” Molina in the article….but then didn’t mention that Janssen has been even better since Molina left.

    In general I’m surprised it’s taken Casey this long to get much credit, especially on this website. Even last year I remember writers on this site speaking glowingly about a closer like Alfredo Aceves coming into the season, while dismissing Casey.

    The guy has been a fantastic reliever for a long while now.

    Career as RP: 303.0ip, 7.8k/9, 2.3bb/9, .286babip, 1.15whip, 2.76era, 3.27fip, 3.47xfip, 3.17siera
    Last 3 Years: 145.0ip, 8.9k/9, 1.8bb/9, .257babip, 0.92whip, 2.36era, 2.67fip, 2.97xfip, 2.57siera

    Vote -1 Vote +1

  14. Bruce says:

    Casey’s cutter is actually very under-rated. It only has good movement – not crazy like Rivera’s – but the movement is late, and he mixes with his 4-seamer enough that he can get a lot of strikes by going back-door to a lefty or even front-door to a righty. His curveball is nasty, but like a lot of weapons, most batters are out by the time they’ve seen it. And his changeup is average, but it’s almost always right after a fastball or cutter, and it’s his ground-ball pitch. He also uses it to get strike 2 and set up the kill with either his fastball or curveball. In other words, Casey is a complete pitcher, and it’s a real privilege to see him work his craft out there. If he keeps on going like this for another 10 years, which I think he can, I think he’ll be in the Hall of Fame some day.

    Vote -1 Vote +1

Leave a Reply

Your email address will not be published. Required fields are marked *

You may use these HTML tags and attributes: <a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <cite> <code> <del datetime=""> <em> <i> <q cite=""> <strike> <strong>

Current ye@r *