The 2015 season was a disappointment for the Boston Red Sox, and that disappointment started with the rotation. The team made a step to remedy that this offseason when they signed David Price to a long-term contract. However, they will still send out four-fifths of 2015’s rotation, and Ian York looks at the PITCHf/x data to answer the question: What can the Red Sox can expect from Rick Porcello in 2016?
Rick Porcello began his Boston Red Sox career with 20 starts that were, frankly, pretty horrible: a 5.81 ERA, 1.44 WHIP, and 5-11 record. He then went on the disabled list, officially for triceps problems, though many fans assumed (perhaps unfairly) that it was mostly an excuse to take him off the mound for a while.
After he returned, Porcello ended the season with an unexpectedly strong set of eight games: 3.14 ERA and 1.20 WHIP, much more in line with the 2014 numbers (3.43 and 1.23, respectively) that prompted Ben Cherington to offer Porcello a four-year, $82.5 million contract extension in 2015.
Which Porcello will the Red Sox see in 2016 – the ineffective one from the first 20 starts of the season, or the post-DL above-average pitcher? Did Porcello make real changes at the end of the season, or was he just as lucky in those games as he was unlucky at the start of the season?
Porcello did pitch differently after his return from the DL. First, he used a different mix of pitches. He increased the use of his trademark sinker (called a two-seam fastball, “FT”, by PITCHf/x) by 10-15% to both left- and right-handed hitters, at the expense of his four-seam fastball (“FF”). He also nearly doubled the use of his changeup, from 12.2 to 23.2% to LHB and from 2.6 to 4.1% for RHB.
(As usual, PITCHf/x algorithms mis-identify many of Porcello’s sinkers and fastballs, even though in this case the two pitches are reasonably distinct. For the charts in this article, I have manually reclassified the pitches.)
Second, there were some small changes in the quality of the pitches, in ways that PITCHf/x can measure. In particular, the speed of his sinker dropped slightly – something that his former catcher Alex Avila emphasized as a key to Porcello’s success.
In this chart, the vertical line indicates the period when Porcello was on the DL. The shaded regions around each line represent one standard deviation of the speed for that game – narrower shaded regions mean less variation in the speed. A couple of things stand out. First, Porcello’s four-seam fastball and his sinker (“FF” and “FT” again) gained more separation in speed toward the end of the season, with his sinker becoming significantly slower than his four-seam. Second, his curve became slower, even setting aside his last game, where his curve velocity plummeted drastically.
Slower pitches give the baseball more time to move, but overall there was not a lot of change in Porcello’s pitch movement after the DL stint. His curve gained some vertical movement, but his most common pitches, the sinker and the fastball, remained fairly consistent.
More importantly, Porcello showed marked improvement of his control after his return from the DL. We have noted before that Porcello’s location is the key to his success, and in the first half of the season Porcello’s location was not sharp; both his sinker and his fastball tended to hit the middle of the plate, and the two pitch types were not clearly separated, both crossing the plate at similar heights. In his more successful close to the season, though, Porcello seemed to fix that. First, his sinker was located more toward the bottom and sides of the strike zone (the grey polygon in the charts below, which are shown from the umpire’s viewpoint) in the post-DL period (the bottom two charts).
While he still threw plenty of strikes, the strikes were now at the edges of the zone, rather than down the middle.
Similarly, his fastball was much less likely to be in the center of the plate, and was clearly separated from the sinker, mainly targeting the upper half of the strike zone as well as the edges.
With these changes, Porcello’s dominant pitch, the sinker, became much more effective. In his first 20 games, batters hit 14.3 total bases per 100 sinkers; in the last eight games, that dropped to just 8.6, a good though not spectacular level. For comparison, that is better than Jon Lester’s 10.9 total bases/100 on his sinker, but worse than Jordan Zimmerman’s 7.4. Porcello also reduced the number of sinkers falling outside the strike zone, to an excellent 29.9 balls/100 pitches.
Porcello’s increased usage of his changeup to lefties was also a good sign. Once again, his location of the pitch improved dramatically. These charts only show the location to left-handed batters, since he rarely threw the change to righties. Pre-DL stint on the left, post-DL on the right:
After returning from the DL, Porcello aimed his changeup – like his fastball – more precisely at the edges of the strike zone. He also added a cluster of changeups that ended up just barely below the bottom of the strike zone, and along with that he drew far more swinging strikes and fouls on the pitch, improving from 24.3/100 changeups to LHB to 36.8/100 in his final eight games.
Porcello opened 2015 by moving away from his strength, his sinker, and trying to emphasize his four-seam fastball. He also seemed to lose much of his normally excellent control, especially of his sinker, perhaps due to overthrowing it. On his return from the DL, he regained his control, threw his changeup more, let the velocity on his sinker drop slightly, and threw the sinker in place of the four-seam.
Does his strong finish predict a good 2016 for Porcello? At the least, it gives us something to watch for when the season starts. Is Porcello throwing more sinkers? Is he separating them from the fastballs, especially in location? Are his changeups to lefties down and away? If so, there may be grounds for optimism.
Ian York uses the PITCHf/x to monitor the strike zone, highlights great performances, monitors league-wide trends and tracks the performances of some interesting young hitters.
Follow Ian on Twitter @iayork.
All data compiled from PITCHfx and Baseball-Reference.com.