Jake Arrieta began the 2016 campaign just as he ended the 2015 season – absolutely unhittable. But as the summer months began to creep in, Jake wasn’t as dominate as he once was. In fact, Arrieta was almost normal. While hitters weren’t actually “hitting” Arrieta, they were able to get on base as long as they remained patient.
| Year-by-Year Comparison | ||
| Year | Hits/Game | Walks/Game |
| 2015 | 4.54 | 1.45 |
| 2016 | 4.45 | 2.45 |
| 2017 | 3.5 | 2 |
It seemed that everyone and their cousin had a reason for the drop off in Arrieta’s numbers. From mechanical to not using his slider as much to the league just catching up to him. We posted several stories on Jake ourselves. Ultimately I believe that the truth was a mixture of all of the things being said. His mechanics were off a bit which caused him to be a little more wild than normal, and the league understood how to approach Jake.
As we step into the 2017 season, there are more questions about Jake. Ones that could point to some extremely dangerous results.
First, let’s do a bit of educating. Major League Baseball has changed the way that they measure a pitcher’s velocity. Brendan Miller at Cubs Insider posted a great piece on the change, which actually educated me on the change (I recommend you read it, and stay for a bit and read the other great pieces on the site).
In a nutshell, it describes how the new system (Trackman) measures velocity from the pitcher’s hand, whereas the old system (PitchFX) measured from about 50 feet away. This, so far, has caused a strange result which I am uncertain they expected (or did). In 2017 pitchers have, on average, thrown about 1 MPH faster than the past. You can see how this data could affect the historical information on a certain pitcher. While it is easy to mark 2017 as the first year of the new method and continue to compile data, how they continue to display the data will be interesting, to say the least.
Now to Jake’s case. With the league adjusting up to about a 1 MPH difference, Jake has gone down in velocity. In 2016 the average Jake Arrieta fastball was measured at 93.7 MPH, so far in 2017, it is 91.1, or a drop of 2.6 MPH, or if you include the increase across the league – 3.6 MPH. Fangraph’s Jeff Sullivan brought up the interesting case and evidenced his case here.
Arrieta last night had 58 pitches tracked, according to Baseball Savant. The fastest was recorded at 92.6, and there were three pitches that cleared 92.0. Compare that to Arrieta’s first start from 2016, when he had 89 pitches tracked. The fastest was recorded at 96.0, and there were 51 pitches that cleared 92.0. I don’t know how many more ways to show you something looks weird. I can’t explain it, but I’d like an explanation.
After Jake’s second start of the season, he hasn’t improved upon his velocity. Through two games his average fastball is sitting at 91.7 MPH, still way down from last season. He has topped out at 93.48 MPH, whereas 2016 he had 51 pitches that were faster than 92 MPH in his first start alone.
Things are a bit more curious if you begin to look at his strikeout figures. Jake had averaged 7 strikeouts per game in 2015, his Cy Young season. That dropped off to just over 6 K’s in 2016 but is up to 8 strikeouts in 2017. With a decrease in velocity, you would assume strikeouts would decrease as well.
So maybe it is movement? A decrease in velocity has added to the actual movement he gets on his pitches?
2015 Movement
2016 Movement
2017 Movement
Eeek! This makes me question Jake’s change up and slider!
Perhaps the answer just lays in Jake’s growth and maturity? Throughout the years, especially pitching at the top of a rotation and pitching in huge postseason games – Jake has become even more of a pitcher.
I agree with Jeff Sullivan if there truly is a drop in velocity it is a scary thing for the remainder of 2017 and Jake’s career. But if he is just maturing as a pitcher, knowing that he doesn’t need to reach back and find 98 MPH in April in order to keep it for October, then I am fine with that.
This isn’t something to completely ignore, and we should certainly continue to monitor his velocity as the season progresses. It isn’t abnormal for a pitcher to have dead arm just after spring training, and it isn’t abnormal for a pitcher to keep some in the tank early, knowing they might make 40 starts in the season. Let’s just hope, for everyone’s sake, it’s the latter.
*Charts via Brooks Baseball
