Nuñez’s slider: A secret to his success?


This afternoon on the Miami Herald’s website, I read this story, featuring an interesting note at the bottom.

Catcher John Baker said Nuñez has been more effective this season because he has added a third pitch to his arsenal, a slider that has kept opponents “off balance.”

“I think last year, guys could just wait on one kind of speed,” Baker said. “Now he has three speeds going.”

Now, when I read this, I have to admit I could not all season remember Leo Nuñez throwing a slider (upon further review, I actually did recall one, and not in a good way, but more on that later). I have taken note of his live fastball and his exceptional change-up, but I did not recall a slider this season.

So, I took to FanGraphs to see if Leo has been using a slider this year, and lo and behold, he was.

According to FG, so far this year Leo has thrown his fastball 52.9 percent of the time and his change-up 39.4 percent of the time. And his third pitch, the slider is thrown about 7.6 percent of the time, which equates to at this point in the season just 16 pitches.

However, according to FG, Nuñez hasn’t “added” anything this year. He’s featured a slider since coming into the majors, using it on a whopping (relative to now) 19.9 percent of the time in 2007. If anything, Nuñez has nearly phased out his slider since joining the Fish, as he is throwing it less often (so far, though that is a small sample size, of course) this season than he ever had, and last year he only threw it 8.5 percent of the time.

Still, this can be a simple misunderstanding, either on my side or on the side of the Herald. No big deal.

That might have been enough to satisfy me usually, as I would’ve just made a personal note to look for it in the future. However, just before I closed the window, I noticed this: The average speed of Nuñez’s slider in 2010 was 84.9 mph. The average speed of his change-up? 86.3 mph.

Now, I’m not a major league hitter or a coach, but I know it is common knowledge that a change-up should be about 8-12 mph slower than a fastball in order to be effective (in that it could be misread as a heater). That leads me to believe that the 1.5 mph difference in speed between Nuñez’s change-up and slider is enough to challenge, if not discredit, the second half of Baker’s quote on Nuñez, as realistically, Leo is throwing at essentially two speeds.

Now this is really getting interesting, so lets got the full nine yards and take a look at his slider with Pitch F/X via Joe Lefkowitz’s awesome site.

Here is a chart of Leo’s 2010 Horizontal vs. Vertical movement on his pitches thus far this year.

If you don’t totally understand this chart, its worth reading up on, but suffice to say that for a right-handed pitcher like Leo, he’d want to see a spread looking something like this.

Now, looking at Leo’s chart we can see that four of these sliders are not exactly what Randy Johnson was throwing. As a comparison, former Marlin Ryan Dempster (also a righty, making him a better comparison for Leo) has long had one of the best sliders in the game. Here is what his HvV chart looks like:

Now you have to look closely, but you can tell that Dempster’s bunch is tighter, and is closer to 0 more consistently on the vertical front, while maintaining a horizontal cut away from the right-handed batter consistently. Those sliders that you see that are shown moving towards the right-handed hitter are the fabled “back-up slider” that is referenced during games occasionally, and while I don’t understand the physics behind them, I know they are not a good thing.

So, when you look at Nuñez’s complete HvV chart this season, next to the “best case scenario” chart showing where pitches should be, you can see that Nuñez’s fastball and change-up are right where they should be and his slider seems to be closer to the inside edge of the chart’s projection.

Based off of that information, you might be tempted to think that Leo’s fastball and change-up are better than his slider.

And FanGraphs would back that up, especially since joining the Marlins. This season Leo’s Fastball is 3.37 runs above average per 100 pitches, and his change-up is 6.05 runs above average/100 pitches.

The slider, over just 16 pitches mind you, is currently at negative-9.47 runs above average.

All right, so all signs seem to be pointing to Leo’s slider not being very good, or very helpful right now. But since there have have been 16 thrown so far, let’s look at them individually.

While I’d love to have a chart for you here, I couldn’t make one easily enough, so you’ll just have to trust me on this.

Of the 16 sliders Nuñez has thrown, all come against right-handed batters. Only two were thrown when Leo was behind in the count (both times 1-0) and he hasn’t thrown any when he has more than one ball. So that should tell you his general confidence in the pitch.

Now of the 16 sliders, only four went for strikes, with none being the strikeout pitch.

Eleven of the sliders went for balls, including four out of five he threw against the Mets in his season-opening disaster (three walks).

The other slider? You might remember it better (as I did) if I told you that Aaron Rowand was the recipient of it.Yeah, it was that tying 2-out gopher ball Leo coughed up in the first game against San Francisco. Interestingly enough, both pitches that Nuñez threw to Rowand were sliders. The first was to the lower-outside corner and was borderline, called a ball. the next caught a nice bit of the plate, and you know what happened.

I think its fair to say that Leo’s two worst appearance this year were the aforementioned New York Mets and San Francisco Giants games. And in those games his slider accounted for four of the 12 balls he threw in three critical walks in New York, and then the dreaded homer to Rowand.

In conclusion

The sample size is simply too small to draw any decisive conclusions, but the information available to us and to John Baker seem to go against his quoted opinion.

The speed difference probably isn’t all that helpful in “adding and subtracting” as they say, while he clearly didn’t “start” throwing the pitch this season (though Baker never intimated as much, from we we can tell from the except).

While it is true that opposing batters might have to keep Leo’s slider in the back of their mind, its probably not keeping them up nights worrying about it.

Nuñez’s strong start to the season seems to be more a product of his increased K-rate and ground ball rate thus far.

Both of those are probably a product of his outstanding and improved change-up, which is probably really the pitch that we and Baker should be talking about.