Boston’s Best Tools 2012: Best Fastball

Moving on to the pitching side of the game, our best tool’s series takes a look at the most essential pitch in most pitchers’ arsenal, the fastball. Pitching coaches and commentators often talk about a pitcher needing to "work off his fastball," meaning that whatever a pitcher’s secondary pitches are, they are just that, secondary. If he cannot effectively use his fastball to generate strikes, whiffs, and weak contact, he is going to struggle. The Red Sox have a few pitchers with elite fastballs. Reliever Daniel Bard is among the hardest throwing pitchers in the game, with an average fastball of 97.7 mph. Among starters, Josh Beckett and his 93.1 mph heater is high up on the leader boards.

Looking at fastballs by velocity does help us narrow in on some of the best ones, but pitching is also about movement and deception. A player who throws a 97 mph fastball might be able to blow by the hitter, but if the pitch is straight and easy to pick up, that speed isn’t going to be enough. What we are looking for is not the fastest pitch (which is Bard’s) but the most effective.

Last season, Josh Beckett’s heater was the most effective by pitch type linear weights system. His fastball was the 11^th most valuable in baseball, worth 15.3 runs saved (above average) over the course of the season. A surprisingly close second was Alfredo Aceves. His heater was even more valuable per 150 pitches and totaled 12.3 runs saved in just 114 innings. If he does secure a place in the rotation permanently, he will be bringing a very effective fastball into the starter’s role. Daniel Bard, who was the Best Tool winner in this category last year, was just fourth in fastball value on the Red Sox with 9 runs saved trailing the departed Jonathan Papelbon. Jon Lester finished a distant fifth (or sixth if you count Wakefield’s 72.9 mph flash of lightning, which I do not).

Best Fastball Candidates: 2011 Fastball Values

Looking at a three year sample of the same data paints a different picture, however. Aceves keeps himself in the conversation here as well, maintaining the highest value per 150 pitches, but Bard takes the top spot. Even throwing his fastball far more often than any other Sox pitcher, he still gets the best results with it, saving 19 runs above average in just 197 innings over the past three seasons. Lester moves up as well while Beckett slides down to fourth place, thanks to his struggles in 2010.

The case is complicated however by considering PitchF/X data on the movement each pitcher has on his fastball. Pitchers who get more of less than the average vertical or horizontal movement on their pitches tend to get better results than pitchers with average movement. In 2011, the pitcher whose fastball distinguished itself the most from others in horizontal movement was Jon Lester. His 93.3 mph fastball moved away from left handed hitters in comparison to the average fastball. A close second was, you guessed it Alfredo Aceves, who like a mirror of Lester, had less than average movement in towards righties.

In vertical movement, Daniel Bard had the most unique pitch; surprisingly his incredible fastball "rises" less than most other pitchers. This may help to explain his consistently strong ground ball rates. It certainly will be an asset to him as a starter, especially since he relies on his fastball more than anyone else here.

Best Fastball Candidates: 2011 Fastball PitchF/X data

Looking at the data above, there is a lot of interesting information. Lester thrives on a pitch that moves away from lefties (at least compared to the average left hander’s fastball) but has also exactly average "rise" on his fast ball. Josh Beckett’s fastball goes the opposite way, tailing in on righties more than average, but once again he has little vertical differential. Aceves and Bard both get less than average "rise" and horizontal movement away from righties, but in nearly inverse proportions.

My fellow OTM writers were not as like-minded on this subject as they were on our Best Power category. Matthew Kory and Marc Normandin both chose Beckett, while lone1c took Daniel Bard. I am going to go with Bard as well, though I think Alfredo Aceves really deserves the runner up spot and maybe even some serious consideration for the top pick. He doesn’t rely on his fastball quite as much as Bard does and you can certainly penalize him (and Bard as well) for having thrown so many fewer innings than Beckett and Lester. Still both pitchers get a ton of value out of their fastballs and the movement their heaters have makes me think they can be as effective in the rotation as they have been in the bullpen.