Mariano’s 2010 dip against lefties

Building depth using the middle and late rounds of the draft
The RAB Radio Show: January 31, 2011
(Chris O'Meara/AP)

By the results, there was nothing out of the ordinary with Mariano Rivera‘s 2010 season. He hit a couple of rough patches, including a period early in the season where his ribs prevented him from pitching in games, but at the end he had delivered his customary sub-2.00 ERA. His peripherals also came close to his 2009 numbers. The biggest difference was in his strikeouts, down to 6.75 per nine. While we typically regard Mo as immortal around these parts, I wouldn’t blame anyone for asking whether this forecasts some trouble for 2011.

While Mo’s strikeout numbers were down across the board, the biggest difference came against left-handed hitters. He still struck out 31 of the 120 righties he faced, 8.90 K/9, but he struck out only 14 of 110 lefties, 4.40 K/9. In 2009 he struck out 35 of 130 lefties faced, or 9.45 per nine. Mo has always been particularly tough against lefties, getting them to hit dinky grounders and humpback liners in addition to the swings and misses. Might this decreased effectiveness against lefties affect his 2011 performance?

In order to determine the answer we have to find the reason why Mo was less effective in striking out left-handed hitters in 2010. Unfortunately, this is not a question which we are readily equipped to answer. It’s more of a scouting issue, and while we’ve learned plenty by watching hundreds of games every year, this is still a question that is better directed towards a trained scout. In fact, it would probably be best answered by multiple scouts, since the differences can be so subtle and nuanced that different people might see it in different ways. But we do have one tool at our immediate disposal: FanGraphs heat maps.

This morning FanGraphs proprietor David Appelman introduced a customizable heat map tool that will make for many pretty visualizations. In his initial post he used Mo as an example. Yet he uses the red-to-yellow heat scheme, and hasn’t set the intensity particularly high. When examining Mariano’s cutter against lefties in 2009 and 2010 I turned the intensity all the way to 100, and changed the format to display more colors. That should give us a better visual idea of what he did in those two years.

The most noticeable difference comes on the pitches slightly out of the zone. In 2009 he spotted the cutter just out of the zone to lefties. It’s harder to hit a ball out of the zone, and we know that lefties have a hard time when Rivera throws his cutter inside. In 2010 you see a concentration of cutters up and in to lefties, but there isn’t that same concentration of balls that run just out of the zone — inside pitches to lefties. We can’t say for sure that this is the sole cause, but it certainly appears to be part of the answer.

Another neat little feature of these heat maps is that it provides pitch type splits. Check out Mo’s four-seamer. He used it effectively against lefties in 2009 when he wanted to pitch them away. In 2010, though, he hardly touched the pitch against lefties. That also might be part of the answer. Perhaps Mo needs to use that fastball to keep lefties guessing.

Again, these heat maps don’t provide us with answers. Instead they put data into a format that we can easily see. Maybe Mo’s lack of strikeouts against lefties had nothing to do with where he spotted his cutter. But more than likely I expect it played a part. That’s his bread and butter, and he just wasn’t ramming the cutter down lefties’ throats as he has in the past. I suspect that he’ll get back to that in 2011.

Building depth using the middle and late rounds of the draft
The RAB Radio Show: January 31, 2011
  • Monteroisdinero

    Heat map inside cutters plus # of broken bats=

    The new Mo stat of effectiveness?

  • J.R.

    I can remember Mo being so dominant against lefties that some switch hitters would face him right handed.

    You know you are good when you do that.

  • Regis

    In the beginning Mo created the heaven, the earth and Yankees Stadium.

  • UncleArgyle

    Glad to see their are legit publications out there, like FanGraphs and RAB, that will acknowledge that Mo doesn’t just throw cutters 100% of the time. It drives me nuts when I hear pundits say “and he only throws ONE PITCH!”. Its “essentially” all cutters, not all cutters all the time. He mixes in 4 and 2 seamers damnit! Anyway, I honestly think Mo is immortal, like Jesus, Duncan MacLeod, and the bad guys in the movie “300” . The day Riviera is no longer awesome, is the day I cash in my 401K and go on a walk-a-bout Down Under.

    • Greg golson

      Who is this RivIEra character you speak of and what have you done with Mariano Rivera? lol

      • UncleArgyle

        Thanks Mr. Typo check. Figures, I look up the proper spelling of Macleod and screw the pooch on Rivera. And I would have gotten away with it too, if it wasn’t for you kids!

  • Thomas

    Mo also threw more cutters away in 2009 than 2010. I wonder if that also decreased his K rate.

  • RobC

    Will Mo ever threw a change up?
    Even just showing it on occasion would keeps hitters off balance

    • Rick in Boston

      I know he’s thrown it in spring training in the past. I wonder if he just has zero confidence in it.

      • bexarama

        I think he’s said it screws up the cutter grip if he uses it too much.

    • MikeD

      Mo used to throw a change in the minors, and when he first came to the majors. It wasn’t bad at times, although he lacked the consistency one needs with a change. It was still a work in progress, but he shelved it once he went to the pen. I also read he doesn’t think the grip works well when trying to also throw the cutter. In other words, we’re not going to see it again!

  • rahboogz

    That’s like saying Jesus’ fish and bread loaves ratio is going down. He still can multiply fish and bread. And Mo can still dominate with the cutter.

  • AndrewYF

    2008 was Rivera’s ‘down’ season. It looks like the majority of his pitches that season were four-seam fastballs, rather than cutters. Was this because Rivera was having arm troubles that prevented him from adding the extra spin to his cutters?

    Amazing that he still put up a 3.15 ERA with mainly a four-seamer.

    • AndrewYF

      Wait, I’m dumb. 2008 was his greatest season ever. 2007 was his down year.

      What is happening with those heat maps? According to FG he threw his cutter 82% of the time that year.

      • MikeD

        I was about to write that any chart showing Rivera throwing four-seam fastballs instead of his cutter is wrong…that is, unless it’s from 1996.

  • Thomas

    He must have stopped spitting on his cutter to lefties.

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    The number 1 blog for the would-be 2000-2010 WS champions, had MLB not conspired against them

  • NJYankeeFan

    I just hope Mo is able to retire before he loses it on the mound. The sight of him turning into Trevor Hoffman and being replaced as closer would be just too much to bear.

  • Jerome S.

    How dare you say His name in name.

    I apologize for this author’s insolence, oh holy one.

  • Short Porch aka Master of the Obvious

    Does anyone have Mo and Russ Martin’s email addresses? That should take care of that.

  • king of fruitless hypotheticals

    I can’t wait for the day he throws a huge looping curve and the batter falls on his ass not wanting to be killed…as it drops in for a strike…to end the game…game seven…tenth inning…1-0 over the Phillies…in New York…

    • Steve H

      After he hits a HR in the 9th to give them that 1-0 lead.

      • fire levine

        You forgot to mention that this happens in 2023

  • Matt

    Those are some very interesting splits you present in the post. What stood out to me about those locations were three things:

    1) Mo seemed to be having much more trouble getting the cutter really in on the hands of left handed batters in 2010. Not only are there fewer pitches on the inside corner, but also fewer that ended up just off the plate in that direction. While it seems that part of this is the pitch selection, in that fewer pitches were thrown in general to that side of the plate, it does seem like he either lost or chose not to utilize one of his weapons in this sense.

    2) While Mo was missing his inside targets, it seems like he was leaving the ball out over the plate where hitters could get more of the meat of the bat on it. In 2009, very few pitches were near the center of the strike zone, but in 2010 there are numerous dangerous locations being breached, including middle-middle and middle-down, which for lefties are likely to result in some damage.

    3) While in 2009 it seems as if Rivera was throwing almost no cutters on the bottom edge of the strike zone, in 2010 the amount seems to have increased somewhat. Since lefties are low ball hitters typically and Mo has lost a few mph off his cut fastball in recent years, it is likely that hitters could be getting to some of these pitches that in the past may have resulted in swings and misses if they were higher in the zone. When Rivera was striking out lefties many years ago, I remember it being commonly on four-seamers up and out of the zone, which he seems to throw more infrequently as well.

    Remember the home run that Luke Scott hit off of him in September? Cutter down. Jason Kubel in May? Down and in.

    Just my thoughts. Feel free to add though if you have other interpretations.

  • Jake

    I’m sure this is a good article, but I just keep looking at that chart and thinking about Predator. Maybe Mariano is a man-killing squid-faced monster from outer space.

  • MikeD

    Mariano’s dip in strikeouts is something to watch, but I’m not too concerned. For one, his velocity in 2010 was the same as 2009. He also has shown this tendency to vary on strikeouts in the past, only to bounce right back, sometimes with a vengence. He dropped from a 9.19 rate in 2005 to a 6.60 in 2006, then back up to 9.34 in 2007. He dipped to a 7.55 in ’04, and had several consecutive years in the 5.28 to 6.90 range in the last 90s, before increasing into the 9.00 range.

    His velocity has decreased from his peak days, but overall nothing alarming, and no change from ’09-’10, while remaining effective. I’d expect a bounceback in strikeouts in 2011, although he has shown he can remain effective even with the lower strikeout rates.

  • virginia yankee

    Mo lost some velocity and with that loss some 6 inches break off his cutter according to one TV game analyst — in a prior year — perhaps as many as 6 or 8 years back the “unfair”, “unhittable'” cutter was reported to have 18 inches of break

    that if true might provide a physics answer

    anecdotally I became frustrated a few years ago by righties who sought to “block” the cutter to right field, it was the only useful approach allowing time to weakly extend the bat and hope — as he lost velocity and movement those have become more purposeful hits —

    He is Mo and if he can mix in another pitch as he added the 2 seamer — he might well pitch until his arm falls off