It is fairly common knowledge that Tim Lincecum is one of the top pitchers in Major League Baseball. He has ranked first, third and fifteenth in the league in Field Independent Pitching (FIP) over the past three seasons, respectively.
Despite the consistent success, Lincecum has had some underlying changes to his repertoire. He burst onto the scene in 2007 and 2008 sporting a 94-mph fastball. Since then, however, his fastball velocity has been in steady decline.
The following table summarizes the loss of velocity by year using BIS data for fastballs, PITCHf/x data for fastballs and—to take out some of the classification issues—Tango’s trick of looking at the top 25% of pitches in velocity according to PITCHf/x.
Investigating an effect
One of the first logical questions when presented with the declining velocity data is, “How big of an effect, if any, does the velocity loss have on performance?” Should it be something we pay attention to this coming season?
Mike Fast found that in general a starter losing one mph will see his runs allowed rise by approximately 0.25 runs, but how can that generalized result be applied to a specific pitcher?
To offer insight into that question, I will introduce two specific data points:
1. Run value per pitch by velocity
2. An at-bat-level metric
What happens if we take a granular view and look at success on a pitch-by-pitch basis? The following graph plots run values per 100 fastballs (rv100) versus velocity over the 2008-2010 seasons. Lower numbers (more negative) equate to a more effective pitch.
There are more variables at play here than simply velocity—sequencing and location to name a few. However, this chart does seem to be evidence in favor of velocity being important to the success of Lincecum’s fastball, at least up to a point.
Velocities between 93 mph and 97 mph all have better run value results than do those at 91 mph or 92 mph. The 91-92 mph range is one Lincecum spends a lot more time in now than he did in 2008. One key distinction to make is that the analysis to this point only focuses on fastballs. The rv100 chart merely shows how the fastball is affected; it doesn’t show how other pitches, or entire at-bats, are affected.
In an attempt to garner insight into that very question, I binned at-bats by counting the number of 94-plus mph fastballs in an individual at-bat and then calculated the weighted on-base avearge (wOBA) against for each bin. The following table summarizes the results:
Again, this table generally points to velocity being helpful to Lincecum’s cause. There are some sample size issues given the low number of plate appearances in some bins, but in general it appears that some 94-plus mph fastballs are better than none. As a whole, the wOBA against when there is at least one 94-plus mph fastball is 0.260 compared to 0.279 when there is none.
The combination of the two presented pieces of data points us towards at least a small correlation between velocity and success for Lincecum, both on the individual pitch level and on the at-bat level.
Adjusting in light of the evidence
Now that I have shown some evidence towards at least a slight correlation between fastball velocity and fastball success for Lincecum, it follows that the next question to ask is, “What adjustments has Lincecum made to maintain success?” The clearest adjustment would be a change in pitch usage as a lesser fastball might not be used as frequently. The following chart summarizes how frequently Lincecum has used his pitches over the three-year span being investigated.
Clearly, the chart shows that he has been less reliant on his fastball as his velocity has decreased, with a good portion of the slack being picked up by his curveball. These data point to Lincecum being aware that his fastball is less effectiveness with less velocity, and he is adjusting his approach as required to get hitters out.
As an addition to the overall usage, I thought it might be telling to see how Lincecum has used his fastball by count over the three-year span. The following table summarizes that data, with the percentages representing the percent of fastballs thrown in that count.
The most telling lines of the table are the 3-2 line and the 2-1 line. Counts where Lincecum had previously been throwing predominately fastballs are now mixed. Sure, some of that shift is probably due to game theory between hitter and pitcher and hitters making adjustments, but some of the change is likely a realization that, if a hitter knows the fastball is coming, it is less likely to be successful than it has been in the past.
Another way to combat declining velocity would be with location. That said, the only point worth mentioning that I could find was that in 2010 he threw approximately three percent fewer fastballs in the generic strike zone than he had in 2008.
Lincecum’s fastball effectiveness and general effectiveness when looked at on an at-bat by at-bat level is affected by velocity. That said, Lincecum has made some adjustments in the way he approaches hitters that seem to have counteracted some of the diminishing velocity. What does this mean for this year? Clearly, he has shown an ability to succeed with the altered approach, but it will still be something to keep an eye on as the season plays out.
References & Resources
PITCHf/x data from MLBAM and downloaded using Joe Lefokowitz’s tool. Other stats are from Fangraphs