Not surprisingly, the fastball represents the majority of pitches used in baseball. On average, 58% of all pitches in MLB this year are fastballs. So that it stands to reason that if a pitcher, or even better an entire pitching staff, can improve the value derived from the fastball, they should see some overall improvement. That happens to be the case for the Pittsburgh Pirates pitching staff.
The best way to currently measure the value from a single pitch is to use the statistic wFB/C. This stat measures the number of runs saved per 100 fastballs thrown. It also allows for easy comparison across teams.
The 2011 Pirates have a wFB/C value of 0.15, meaning that 0.15 runs are saved for every 100 fastballs thrown. This only ranks them 19th in baseball, but it’s the improvement in this statistic that has been more important to the Pirates resurgence. Last year the Pirates staff had a wFB/C value of -0.80, ranking them last in MLB. The 0.15 posted thus far marks a year-over-year increase of 0.95, the best in the majors. And just to show how important an improved fastball is in baseball, note that the top five teams in wFB/C improvement have a winning percentage of 0.537 in 2011 versus 0.431 in 2010 (a significant increase of 0.106). The bottom five teams in wFB/C change have a winning percentage of 0.442 in 2011 versus 0.508 in 2010 (a decline of -0.066).
Knowing the above, the next question is whether the Pirates will be able to maintain a positive wFB/C value and continue to compete in the second half. Since this stat is generally looked at as being more descriptive than predictive, it’s hard to say exactly where a pitcher will end up year-over-year. However, there are three important pitchers on the Pirates staff that have over-performed with the fastball versus the past two seasons and thus deserve watching.
First is Paul Maholm, a Pirates starter who has thrown the most innings for the team this year. His wFB/C is currently 0.74, but that’s come after values of -0.96 in 2010 and -0.50 in 2009. The second is starter Jeff Karstens, who has posted a 0.98 wFB/C after seasons of -0.96 and -0.76 in 2010 and 2009, respectively. The third pitcher to watch is closer Joel Hanrahan. His wFB/C in 2009 was a respectable 0.86 in 2009, dropped to -0.94 in 2010, and is now currently at 2.11, placing him in the top 15 amongst all relievers.
The improvement with the fastball has definitely been one of the many factors that have lead to the Pirates improvement this year. If the pitching staff, and especially the three pitchers noted above, can continue their success with the fastball, the Pirates should remain competitive down the stretch.