Wakefield’s Fastball Redux

A couple weeks ago Other Dave noticed that Tim Wakefield has one of the best fastballs so far this year. He suggested that Wakefield’s fastball is so successful, despite working in the low-70s with average movement, because it is a good 7 or 8 mph faster than his knuckleball and keeps hitters off balance. I really liked this idea and wanted to see if Dave was correct.

So I went through and looked for at-bats in which Wakefield threw a fastball after throwing at least one knuckleball in that at-bat, and found the difference in speed between that fastball and the knuckleball that immediately preceded it. First let’s look at the run value of a fastball based on its speed, the black line is the average and the gray standard errors. The run value is the change in run expectancy after the pitch, so a negative number is good for Wakefield.


To begin with notice that his fastball is quite good, -0.02 runs per pitch is -2 runs over 100 pitches, which is great. Interestingly after Wakefield’s fastball gets up around 72 mph there is no increase in effectiveness with an increase in speed. This is pretty surprising, generally the faster a fastball the better the outcome. Now let’s look at the run value of a fastball based on how much faster it was than the preceding knuckleball.


Here you see a clear consistent, if noisy, trend. As the fastball gets faster compared to the previous knuckleball its success increases. These two graphs together tell us that it is not the absolute speed of Wakefield’s fastball that determines its success, but its speed relative to the previous knuckleball.

Just as Dave suggested the success of Wakefield’s fastball is indeed tied to how much faster it is than his knuckleball, and since his knucleball is so slow he can be effective with his low-70s fastball.

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Dave Allen's other baseball work can be found at Baseball Analysts.

10 Responses to “Wakefield’s Fastball Redux”

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  1. Big Oil says:

    Very cool analysis; I don’t know how possible it would be, but a similar breakdown, refined along the lines of his knuckleball being “on” or “off”, would shed an interesting light on the fastball success vis a vis movement on the slower knuckler. I suppose you’d have to have some sort of movement criteria, perhaps derived from pitch f/x, to do so.

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  2. Alireza says:

    Does Wakefield still sometimes use an Eephus pitch? I remember seeing him eat Tim Salmon alive with one around 1995-1996.

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    • Marcel says:

      He throws a big, slow curve; not really an eephus, but obviously much slower than the average pitcher’s curve.

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  3. Davidceisen says:

    With as big as the error bars are there is very little clear and consistent about the graph. They are one standard deviation right? It looks like around 8.5 the top range of the error bars is just lower than the bottom range of 2.1, and other than that the error bars overlap. It’s a nice graph, but the noise makes it impossible to make any valid claims–most likely due to a small sample.

    Maybe doing the same graph for the last few years may be insightful? It seems that Wakefield has had an above average fastball the past three years.

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  4. Steve Shane says:

    from the handful of wakefield games Ive seen the last 2 years, it seems like he only throws his fastball in 3-0 or 3-1 counts, when the batter is probably taking anyways bc its not like wake can control where he throws his knuckleball.

    This year after a 3-0 count there have been 15 BB 2 HBP and 3 H in 10 official ABs (.741 OBP)

    After a 3-1 count, 20 BB 3 HBP and 7 H in 30 offical ABs (.566 OBP)

    So it seems like the reason why wake has such a “good” fastball is bc whenever he throws it, the batters arent swinging, thus arent hitting XBHs…

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    • DavidCEisen says:

      That’s interesting. If that is true batters should expect a fastball, and since Wakefield has such a below average one (in terms of speed and movement) they should be destroying the fastball. Is it possible to chart the count for when Wakefield throws his fastball?

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    • Hizouse says:

      I went to the Braves-Red Sox game Sunday and thought the same thing. There should be a lot of taken strikes on his fastballs, which would reduce the run value. Dave A, can you compute the run value only on pitches when the batter swings?

      Also, the only time I noticed a fastball on a non-3 ball count was to opposing pitcher Vazquez, so that may be a factor also (bad hitters see more Wakefield fastballs–though I suppose that’s generally true for most pitchers).

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      • Steve Shane says:

        I watched that game and there was one inning where wake went to a 3 ball count on a batter and threw a fastball for a strike, the next batter went to 3-0 and wake threw 2 straight fastballs for strikes, and I couldnt believe the 2nd batter didnt “expect/prepare for” a fastball especially after he already threw one on the 3-0 count.

        Im sure its hard to hit a 70 mph fastball when youre used to 90-95 mph but I would assume every MLB hitter should crush it if they know its coming.

        I think most people, besides the Buchholz’, are fans of wakefield.

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  5. Snook says:

    Interesting article. No matter what it proves I have been a Wakefield fan since he almost beat the Braves his rookie year in the playoffs by himself.

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