First of all, I want to apologize in advance for the general tenor of this post.
I don’t want to be that guy. The team is playing great, 17 – 4 in August, just swept the Dodgers in LA and is sitting at the top of the Wild Card race and now has a 57% likelihood of making the playoffs, according to Fangraphs. Everyone’s excited. The fans are fully behind the team. Hell, even Cards twitter has become a relatively nice place to be. I’m not that guy. I either mute or choose not to follow all the negative Nancies out there always complaining about this or that on Twitter so I surely don’t mean to be the guy to rain on everyone’s parade. But the bullpen still scares me.
The list of grievances caused by the Cardinals’ bullpen this year is long enough for Martin Luther to seek out a ghost writer. The pen is one of the primary reasons the Cardinals struggled so for the first half of the season and one of the main reasons that Mike Matheny ultimately lost his job. When the team fired Matheny on July 14 it had a 47-46 record. The Mike Shildt era began with a win but the team was still sort of just treading water for the next couple of weeks. On July 27, the team was still at 1 game above .500 (52-51) and that’s when the purge occurred. On that day the team jettisoned Sam Tuivailala to Seattle, Brett Cecil to the disabled list, Tyler Lyons to Memphis (via DFA where no other team claimed him) and Greg Holland to the trash heap. From Memphis arrived Daniel Ponce de Leon, Tyler Webb, and Dakota Hudson and a couple days later the team traded for Chasen Shreve from the Yankees.
On the surface, the bullpen has been lights out since the purge. The pen’s ERA over the last 30 days has been 1.86 (tops in the big leagues) over 97 innings. It has 12 saves (#1 in MLB) and 30 shutdowns (4th) over that time period. Nearly all of the individual relievers have been fantastic as well. Jordan Hicks has a 1.98 ERA over that time. Bud Norris is at 1.54. Shreve is at 2.45. Hudson is at 1.29. Tyler Webb, Austin Gomber, Tyson Ross, Carlos Martinez (all in relief) are at 0.00. Even Cecil has yet to give up an earned run since he returned from the DL. The highest relief ERAs in that time period are Luke Weaver’s 3.86 (in just 2.1 innings) and Mike Mayers’ 3.60. In those 97 innings, the pen has given up a total of 23 runs and just 65 hits.
The underlying peripherals, however, are a little scary. The team’s K rate over that time period is just 20.3%, 24th in the big leagues. The walk rate is nearly 12%, 3rd worst in the big leagues. Their BABIP against is an unsustainable .224. Their FIP over that time period is 3.96, obviously much higher than their ERA. At least the FIP is still around league average. What the pen has done very well is keep the ball in the yard. Their 0.65 HR/9 over the last month is 2nd best in the majors but it’s fueled by a (probably) unsustainably low 7.9% HR/FB rate. So while the team’s bullpen was retooled considerably a month ago and while it ostensibly led to a huge improvement in the pen’s performance, it’s highly dubious that the performance can continue.
The thing is that FIP assumes that pitchers have no control over batted balls upon leaving the bat and we know that’s not entirely true so maybe there’s something in these results that is sustainable. League average exit velocity for the season is 87.8 mph and the good news is that most of the team’s relievers have allowed an exit velocity over the last month less than league average. Hicks and Mayers are at 87.2 and 87.4, respectively, but the other 2 guys that Mike Shildt seems to trust the most in high leverage situations – Hudson and Norris – have allowed exit velocities over the last month of just 82 and 83.4 mph, respectively. Hudson has walked as many batters as he’s struck out and his K rate in the big leagues has been less than 15% but at least he’s not allowing any hard contact at all. To wit, he has a 63.2% GB rate since being called up. One can get a lot of outs even without strikeouts if the batters just pound the ball into the ground. His average launch angle against is -1.1 degrees. Over the last month only 9 relievers in the big leagues have allowed a negative launch angle against in more than 20 balls in play.
Still, it’s hard to see that these results are sustainable. Of the 13 pitchers who’ve pitched out of the Cardinals’ pen in the last 30 days, only 3 have a wOBA that’s higher than their expected wOBA (which would indicate possible bad luck). The other 10 all have a wOBA against that is lower than their expected wOBA which indicates that their results have been better than one should expect based on the way they’ve pitched.
Norris is the one whose results have most closely matched his expected results as his wOBA against is just 16 points lower than expected. Hicks’ wOBA is 42 points lower than expected. Hudson’s wOBA is 88 points lower than his still good expected wOBA against. Ross, Weaver, and Cecil – despite pretty good results over the last month – just haven’t been good.
Despite the negative tone of this post, we should recognize that the team’s most important relievers at this point – Norris, Hicks, and Hudson – have still pitched pretty well of late. They just haven’t pitched as well as the results have indicated. And the pen has added Martinez to the mix which obviously makes it stronger and also lengthens it, lessening the need to use some of the relievers who aren’t quite so good.
It's reasonable to expect Martinez to pitch quite well in relief – assuming he’s healthy – and for the others to pitch relatively well. Make no mistake, the pen is better than it used to be. Holland wasn’t good. Lyons was terrible this year. I was never the biggest Tuivailala fan and the team will certainly benefit from Cecil getting fewer and lower leverage innings. But it’s probably also reasonable to expect some regression to the mean over the last month-plus of the season. The way they’ve pitched over the last 30 days is probably an aberration and the offense, defense, and starters are going to have to pick up a little of that slack if the team is going to make that playoff push.