E-Rod’s cutter has been a surprisingly effective pitch
Featured image courtesy of Zimbio.com: (May 9, 2018 – Source: Mike Stobe/Getty Images North America)
After Eduardo Rodriguez exited in the 6th inning of last night’s game against the Atlanta Braves, I had a weird calling to write about him. This “calling” was not prompted by anything out of the ordinary (good or bad) that E-Rod did in last night’s start. In fact, his 5 and 2/3 innings of 2 earned run ball with 7 strikeouts and 3 walks was, by all accounts, a typical start for the southpaw.
On the season, he has become very consistent at his craft and the book is pretty much out on how his in-game performance usually will go. For starters, he always manages to rack up a hefty amount strikeouts (10.90 K/9) but that is at times offset by his tendency to give up hits. Subjectively, it feels like he is working with runners on base quite frequently. Moreover, he has trouble getting past the 6th-inning mark, exceeding it just once in 2018 (6 and 2/3 innings against Toronto).
With that said, he has really found a nice rhythm over the past four starts. In those 21 and 1/3 innings, Rodriguez has pitched to the tune of a 2.11 ERA, striking out 26 batters and walking just 6. Not surprisingly, he has not gotten to the 6th-inning mark in any of the starts. Still, he has pitched well, looking like the epitome of a solid mid-to-back of the rotation piece. At the very least, he has become an embodiment of consistency for Boston.
Put it all together, and he has compiled 4.02 ERA and 3.61 FIP in 53 and 2/3 innings this year. His ERA has improved a tad from 2017 (4.19) but the noticeable improvement can be seen from his underlying stats, his FIP. FIP stands for Fielding Independent Pitching and it strips out all batted ball variance (anything hit into the field of play) in its calculations. Instead, it looks at three factors (strikeouts, walks and homers) which are entirely in the pitcher’s control and not contingent on the defense behind him. It is scaled to an ERA-scale and has been proven to have more predictive value than ERA.
Anyway, his FIP was 3.97 in 2017, so it should be clear E-Rod is achieving better results in this statistical category. The biggest reason for this superior total is his bump in strikeouts, but his small decrease in walks and homers play a role as well. Whenever there’s a conspicuous improvement for a player, it is worth exploring more in-depth. I mean, he’s come a long way from the 7.25 K/9 he posted in his 2015 rookie season with the Red Sox.
Now, Rodriguez’s performance has not been leaps and bounds better than it has been in the past. Regardless, he has been different, an enhanced version of the Eduardo Rodriguez we have become accustomed to seeing. People have sensed the potential has always been alluring, with stuff that has been raved about by pundits. Outside of FIP, he is generating a much higher percentage of groundballs this season (from 34.9% in ’17 to 42.1% this year). Balls on the ground, generally, are converted to outs more often than flyballs and line drives and do not go for extra-base hits nearly as often as the others.
So, we are now aware that he has improved his strikeout and groundball rate in 2018. Honestly, that explains why he has been a slightly more effective pitcher, but, because we are all intellectually curious individuals, we want — nay, need — to know the why for his improvements. In other words, why has he been able to attain more strikeouts and groundballs?
Well, without detailing the boring process of how I arrived at the semi-answer, there is something considerably different about Rodriguez’s 2018 pitch selection. After throwing zero cutters in 2017 and just a few in 2016, E-Rod has delivered 111 cutters on the season this year, which works out to be 12.31% of his pitches, according to Brooks Baseball. A cutter is defined as a pitch that resembles both a slider and a fastball, but really exists between the two offerings. It typically move towards the glove side with quite a bit of movement (like a slider) but is thrown demonstrably faster than a slider (like a fastball).
Rodriguez’s cutter averages close to 90 mph with 4.97 inches of vertical movement this season. Here’s the pitch’s usage over the course of the 25-year-old’s (yes, he’s still that young) career, courtesy of Brooks Baseball.
I removed his other three pitches from this chart (changeup, slider and sinker) so the new pattern becomes obvious. He is using the cutter more than ever before at the expense of the four-seamer and slider. The changeup and sinker rates do not seem to be affected much at all. He deploys the cutter against right-handed hitters (13%) more than left-handed hitters (7%), using it most frequently when he gets ahead of righties (19%).
You probably want to see the pitch in action, so below I have embed a video of E-Rod utilizing the cutter in 2-2 count against right-handed swinging Andrew Susac to the end the inning. Against right-handed hitters, he throws the pitch in two-strike counts 15% of the time.
It is a beautifully executed pitch, appearing to be off the corner but cutting right into the middle of the plate (albeit low) for the punch out. A cutter is designed to stay down in the zone just like the one to Susac and that is exactly where he has stayed with the offering all season, typically hanging around the lower corners in, and just outside, the strike zone.
Rodriguez’s 2018 cutter has been whiffed on 7.21% of the time, which is not an inordinate amount and not surprising for a cutter. It has, however, yielded the second-highest GB% of any of his pitches, with an 8.11% of total outcomes. Only his changeup, which is by far his best pitch (although, he has a formidable 4-seamer), has compiled a higher percentage (10.99%).
Despite hitters producing an unsustainable .471 BABIP (batting average on balls in play) against it, hitters have mustered a lowly .333 slugging percentage and have yet to record an extra-base hit against it. It is apparent the pitch’s forte is eliciting weak contact and, for a guy who has above-average swing and miss offerings (4-seam and changeup), the cutter mixes in nicely.
It is not an entirely new pitch because we saw introduced in late ’15 through early ’16, but it seems he has finally found a way to use it consistently and effectively. For what it is worth, this month has seen him throw the highest-percentage of cutters in his career and, in the same span, he has had one of the best stretches in his young career. The cutter gives Rodriguez a whole other weapon to use against hitters, allowing him to mix up his game plan. It has aided Eduardo Rodriguez in being a better, more reliable pitcher in 2018.