The Mariners’ bullpen has been one of the best in the MLB. To date, they rank 6th in bullpen WAR. While they have pitched well, they haven’t necessarily been the most lights out group in the league. More precisely, their bullpen ERA (3.73) is ranked 13th in the league, while their bullpen xFIP (3.83) is good for 7th. While these numbers aren’t necessarily elite, they’re certainly nowhere near bad.
Chasen Bradford has been as good as you can expect from him. James Pazos has been stellar. Edwin Diaz has been one of the best in the league. Juan Nicasio, though, has not been good.
That’s weird to say, because Nicasio has, in his own way, been good! He has faced 123 batters thus far while striking out 38 and only walking 2. That’s great! His 5.16 ERA? Not great.
There are many signs that Nicasio hasn’t gotten a fair shake. Of relievers with 20 or more innings, Nicasio is the 30th ranked reliever in xFIP. His 29.3% K-BB% is 11th. On Baseball Savant’s xwOBA leaderboard, Nicasio has one of the most extreme wOBA-xwOBA differentials in the MLB.
His wOBA currently checks in at .334, while his xwOBA is .286. That’s good for a .048 differential, which is the 5th most extreme in the MLB, and not extreme in a good way. By this measure, Nicasio is the fifth unluckiest pitcher in the MLB. You could say, then, that Nicasio is just suffering from bad luck.
Something isn’t right though.
His current K/9 (11.53) is well above his career average, and easily higher than his 2017 K/9 of 8.96. If anything, it seems off that his BB/9 is too low. Numbers are bound to fluctuate, but there doesn’t seem to be any evidence that Nicasio has developed pinpoint command, as he’s nearly 32 years of age.
What’s odd is he isn’t *actually* throwing in the zone more. A cheap way to lower one’s walk rate is to pound pitches in the zone. You may not be very good, but you’ll surely stop walking players! Nicasio’s in-zone % is almost exactly the same for his four-seamer, and it has actually dipped to a career low for his slider. Overall, his in-zone % is down from 54.4% to 51.6%, but it is nowhere near his career low of 47.6%.
His batted balls, though, have changed. The MLB league average launch angle is 10.8 degrees. Last year, Nicasio’s average launch angle was 10.8 degrees. That ranks 376th out of 673 qualified pitchers and was, by definition, league average. This year, it’s jumped massively to 17.0 degrees, which is 96th out of 534 qualified pitchers. (Weird side note, one thing I noticed was that Wade LeBlanc has been next to Nicasio on the launch angle leaderboards for both years. While LeBlanc has been better, Nicasio has been worse.)
It’s clear that something is up with his slider. It’s being offered at less than ever, and when hitters do swing, they’re missing less. When they connect, they’re having more success with it. Ground balls are down while line drives, slugging percentage, and isolated power are up.
According to FanGraphs, Nicasio’s slider has never been worse. his wSL/c (the weighted value of his slider) is -3.55. Over his career, it has fluctuated from below average to above average, but it has never been this bad.
Consider the following gif of Nicasio’s slider in 2017 vs. 2018:
That… is much different. Nicasio’s zone percentage numbers on his slider may not have changed significantly, but his pitch location sure has. This year, Nicasio has pitched his slider almost exclusively on the corner of the plate, while last year he pitched over the middle of the plate much more often. He’s nibbling.
The pitch itself has changed, too. In 2017, Nicasio had a different slider than he has ever had before. That’s a good thing! The old one wasn’t good. This year, it appears to have reverted to its previous form.
Here is a table:
Tables aren’t always easy to read! Here is a graph:
I made it incredibly easy for you. So incredibly easy that I even went into MS Paint and added poorly drawn arrows!
Nicasio’s 2015 and 2017 sliders are good! His 2016 and 2018 sliders are not. It turns out, it doesn’t matter if Nicasio is getting a lot of vertical movement or horizontal movement, he just needs to be getting a lot of one of them. His 2016/2018 sliders didn’t get enough horizontal or vertical movement, and therefore are not good pitches.
It’s plausible that multiple things are going on here. First, Nicasio has been on the wrong side of luck — a lot. Second, there are things that are amiss with Nicasio. His slider is different, and his velocity is down. It may not be a coincidence that in 2015 and 2017, Nicasio had the best sliders of his career. He had the fastest pitches of his career. With the velocity has went his movement, and with his movement went his effectiveness.
As I wrap up this post, Nicasio has just given up three runs and the lead to Boston. Nicasio is probably (hopefully?) fine. His velocity and slider movement issues don’t change that fact that the actual batted balls that he’s induced suggest that he has been pretty solid. Last year, his wOBA against was .265. This year, his expected wOBA is .286. If his expected wOBA was his actual wOBA, he would be tied with Charlie Morton, Clayton Kershaw, and Tyson Ross. Not at all bad company! That, unfortunately, is not the case, and also not how things work. Baseball Savant’s expected batted ball data is imperfect. Juan Nicasio, really, is imperfect. But, this information can shed enough light on what’s going on that maybe we can stop crucifying Juan Nicasio for his struggles.