The Cardinals' pen likely to bounce back; still likely to be upgraded at the deadline

As we've talked about at length this year, the Cardinals' 2015-2016 off-season was all about building depth. Jedd Gyorko, Mike Leake, retaining Jonathan Broxton and  Brandon Moss, yada, yada, yada. You guys know that, you've been inundated with it. It's worked out pretty well so far. Enough of the position players have been hitting that they've been able to avoid giving plate appearances to the guys who haven't been hitting, even if that means playing Matt Carpenter at second again, or putting Stephen Piscotty or Kolten Wong in center. After a rough start to the year, the starting rotation has picked it up and been about as good as we were expecting (I mean, I shouldn't speak for everyone here I guess, but that's the general vibe I think).

Before the season, the Cardinals seemed to me to have a deep enough pen that they would handle whatever was thrown at them. Even without Jordan Walden, the team had a bullpen stocked with seven realistically good options for Matheny to turn to, with a few other arms in the minors who could fill out the seventh spot admirably. But then baseball had to do that thing where things happen entirely different from what you were expecting. Here's all eight relievers (not counting former secret bullpen weapon Ruben Tejada) the Cardinals have used this year, first showing you their projections before the season, then their 2016 numbers, and the differences between the two. As usual I will use an averaged combination of Steamer and Zips, the two best public projection systems available:

I'm sure you were expecting to see that Oh has done much better than expected. Bowman has been another bright spot. Literally everyone else has done worse than expected. Trevor Rosenthal is getting all the attention for his very untimely under-performance, but Kevin Siegrist has been even worse by both FIP and xFIP. Rosey hasn't even been the worst under-performer, as that title goes to Tyler Lyons and his ridiculous homer problem so far this year; nearly 30% of his fly balls have gone out of the park this season. Lyons looked like an intriguing left-handed specialist before the year, but he's given Matheny no reason at all to move him out of his low-leverage long-reliever role. Broxton was expected to be cromulent by the projections, but his xFIP has been worse than everyone but Seth Maness.

At 15th in FIP on the year, the bullpen hasn't exactly been a dumpster fire. It has, however, been the team's weakest link. The offense currently ranks 2nd in non-pitcher wRC+, and the starting rotation, despite it's troubles, ranks 12th in WAR in the majors, and 8th in the last 30 days. The defense leaves a lot to be desired, but that's intertwined with the good hitting.

How should this affect our perception of the pen going forward? According to the projections, not all that much. Here's a bar graph, showing three bars for each player: (1) projected FIP going into the season, (2) FIP so far this year, and (3) projected FIP for the rest of the season (ROS):

Oh's value has increased a nice chunk, as has Bowman. As you would expect, everyone else went in the wrong direction, but they've been fairly marginal losses. All in all, the projections actually see the Cardinals bullpen as the 8th best going forward. Here's one big reason for that: the bullpen has been third best by xFIP (for an explanation on xFIP and it's difference from FIP, click here). The Cardinals have the fourth largest positive difference between their bullpen's FIP and xFIP, due to holding the sixth largest HR/FB rate in the game. That's certainly not going to continue going forward, even if Matheny anoints Lyons as the team's only reliever.

Another reason why the projections haven't completely fallen off is that these players do have track records for success. Rosey, Siegrist, and Maness have all been important cogs in the Cardinals' bullpen the last few years, save for an ineffective and injured Siegrist in 2014. The projections don't simply forget that, and you shouldn't either.

Considering we're talking about relievers here in less than half a season a work, there's also the necessary mention of sample size. Rosenthal, for instance, has only thrown 24 innings this year. At 24 innings into 2016, pretty much all of the Cardinals' starting pitchers looked bad, and pretty much all of them look much better now. That's not to say that they will all necessarily turn it around, just that it's too early to say that this is their new skill level.

So at this point, I do expect the Cardinals' bullpen to bounce back, even without reinforcements. But that doesn't mean the team shouldn't be planning ahead, and considering any additions before the deadline in case it doesn't work out that way. The Cardinals still have two options down at Triple-A, here are Miguel Socolovich and Sam Tuivailala's stats on the year:

Of course, you would expect these numbers to get a little worse when pitching against major league hitting, but even with some inflation in those numbers, they look like they'd get by fine in a major league pen. Unless the team calls up Alex Reyes for late inning duty, these are the best the org has in house. The Cardinals have traded for major league talent at the deadline each of the last seven years though. The most common acquisition at these deadline deals have easily been relief pitchers, such as Octavio Dotel, Edward Mujica, John Axford, Steve Cishek, and Broxton. While the pen will most likely be better going forward even with no move, I'd expect GM John Mozeliak and company to be opportunistic in trying to add one more reliever that they like in order to solidify things as they contend for a historic sixth straight playoff appearance. The team has done exceptionally well at acquiring these relievers for little in return, and hopefully that continues in 2016.

The plan would then be: Oh as the bullpen ace, whether that's as the closer or not. Bowman as an option mostly in the 6th and 7th inning like he's mostly been used, with the team acquiring someone in-between those two in skill level who could help cover all the high leverage situations that come up throughout a 162 game season. The team would then hope for a few bounce backs from the other guys, eventually establishing a new hierarchy to the pen for the stretch run and hopefully some October fun.

....And, you know, move Rosey out of the closer's role, for now. He's a big man, he can take it, and Oh is pitching at an elite rate. I expect him to get right and be awesome again in the near future, but something is clearly not working right now, and every game is super-important.