Andrew Miller makes the bullpen a strength rather than a liability


A few weeks back, I wrote extensively about the Cards’ bullpen needs and encouraged them to be aggressive with their pen. At the time I really didn’t even consider Andrew Miller to be a very good option because I expected him to get too much money. I felt the Cards needed to add 3 bullpen arms and really couldn’t afford to spend too much on any one of them who wouldn’t be the closer. The fact that the team was able to add Miller yesterday by only guaranteeing him $25 million should be considered a tremendous coup for the organization.


The Cards need to improve their pen’s K rate perhaps more than any other team in baseball after finishing last season with the 6th lowest strikeout rate in baseball. Unsurprisingly, the team’s bullpen finished in the bottom half of baseball in ERA, FIP, WAR and it was 2nd to last in WPA. In short, the team’s bullpen was terrible in 2018 – possibly costing the team a playoff spot – and needed a huge infusion. The addition of Miller provides that infusion.


Earlier as part of that bullpen series, I determined that the most important thing to look for in terms of a reliever’s stats when projecting his future performance was the difference in his strikeout rate and his walk rate. Other things matter, too, but the guys who strike out lots of guys and don’t walk very many are, all things being equal, going to be more successful than those who don’t do those things.


Below you’ll see Miller’s K rate, BB rate, and K-BB% (the 3 columns on the right) for the last 7 seasons and you’ll notice that he has been dominant for the entire time period.



Some will point to Miller’s age (33) and the fact that 2018 was his worst season in the last several that maybe Miller isn’t the investment the team needs at this point. I respectfully disagree. It’s true that he was injured during much of last season, battling shoulder, hamstring, and knee issues but, according to Derrick Goold, he’s been checked out by the Mets’ team doctors and the Cardinals have reviewed those results. Everyone seems to think he’s going to be tip-top when the season starts.


And tip-top is really good. As the Post-Dispatch’s Ben Frederickson pointed out, Cards’ lefty relievers last year stunk like fresh garbage and Miller would have been a huge improvement even at his worst. Even if there’s literally no improvement from 2018, Miller still adds a lot to a team that was going to be counting on getting a lot of outs from Chasen Shreve and Brett Cecil.


For his career, lefties have a feckless .223/.319/.338 line against Miller but that includes the early years when the Marlins and Tigers were trying to make him a starter. In his last 6 seasons, lefties have only had on-base percentages greater than .300 twice. They’ve slugged .213 and .250 against him the last 2 years.


This is particularly important because the Cards will play nearly half their games against other NL Central foes and Miller’s skill against lefties is going to come in really handy against the likes of Anthony Rizzo, Kyle Schwarber, Joey Votto, and Christian Yelich. There are a lot of good left-handed hitters in the NL Central and it’s going to take a really good lefty reliever properly deployed to get them headed back to the dugout where they belong.



For their careers, Rizzo is 2-8 with 4 K’s and no HR’s against Miller. Schwarber is 0-4 with a walk and a K. Votto is 1-3 and Yelich is 0-1 against him. Now, these individual stats aren’t predictive but they do show how tough he can be on lefties and also that these hitters haven’t seen too much of Miller in their careers.



Some may point out that there were other lefty relievers on the market and the team could have saved money by signing one of them. While that’s true, Miller also offers the ability to get right-handed hitters out, something that really can’t be said of Tony Sipp, Justin Wilson, or Aaron Loup. Those guys are pretty traditional LOOGY’s but Miller can be – and often has been – trusted even with the toughest right-handed hitters. Since Miller has really blossomed into one of the game’s top relievers 6 seasons ago, righties have averaged a .158/.260/.261 line against him. That includes last season when he battled injuries and frankly wasn’t very good against them.


Miller is basically a 2-pitch pitcher, setting hitters up with a mid-90’s 4-seam fastball. His money pitch, however, is a low-90’s slider that is as close to unhittable as you can get. The whiff rate on Miller’s slider from both righties and lefties last year was 37.4%, down from 46% the season before. The gif below, brought to you by the fantastic @cardinalsgifs shows you what one of his sliders can do to a right-handed hitter.



Miller clearly then makes the Cardinals’ bullpen a lot better and it’s pretty easy to imagine how he might be deployed. Mozeliak was careful to say that Miller was not necessarily the closer but would be deployed strategically to take advantage of his strengths. So I can see him being used to close out a game if Rizzo is due to come to the plate in the 9th, or even as early as the 7th if Rizzo might bat in a high-leverage situation that early. Because both he and Jordan Hicks have the ability to blow hitters from both sides of the plate away, it’s pretty easy to imagine that those 2 might be entrusted to get out the last 9 batters of a game. One would set up and the other would close depending on which hitters were due for the opposing team. Put those 2 guys together with the underrated John Brebbia and I can imagine Mike Shildt feeling pretty comfortable at least with the last 3 innings. That would leave guys like Shreve, Dominic Leone, Luke Gregerson, and whoever else is down there to get through the 6th and get the ball to the big 3.


In 2018, the Cards’ bullpen had 0.5 fWAR (MLB average was 3.4) and had a win probability added of minus 4.54 (MLB average was around +1.6). Any way you slice it, the Cards’ pen last year was terrible and contributed perhaps more than any other element to the team’s not making the playoffs. Adding Paul Goldschmidt was a huge step in bolstering a lineup that needed a jolt. Adding Miller not only makes the bullpen significantly better, but it also lengthens the pen’s ability to get outs. It’s not just that Miller will get batters out, but the fact that he can get more than 3 outs if needed and dominate righties and lefties alike takes a lot of the pressure off the other guys to do their thing.


For more on what Miller has done and can do, I encourage you to read this piece by our own Ben Cerutti.


Thanks to @cardinalsgifs for his help with this piece.

Stats come courtesy of Fangraphs, Baseball-Savant, and Baseball-reference.

Thanks to you all for reading.