Wait, the Cubs Bullpen is…Good?

When the Cubs’ resurgent relief corps went six scoreless innings to preserve the win last night, I really wanted to start firing of paraphrased MiggyMont hashtags saying #thebullpenisgood. And while I was well aware of the hidden bovine baby-maker joke, I felt that my intent might perhaps be a bit too esoteric to share in a format like Twitter.

Had you told me a month ago that five Cubs relievers would carry the team through two-thirds of a game while allowing only 2 hits and walking none, I’d probably have laughed in your face. If you’d have told me Travis Wood and James Russell were a part of the effort, I’d have backed slowly away from you. But that’s exactly what happened last night.

While it had often borne the brunt of the blame for the inconsistent performance of the team as a whole, the bullpen really is good. Or perhaps a better way to say it is that the bullpen has been good of late.

https://twitter.com/carriemuskat/status/609048757074825217

That performance hasn’t necessarily translated to wins though, as the Cubs have gone a mere 9-8 over that stretch. Then again, 11 of the 17 games came against the likes of the Nationals, Royals, and Tigers, all of whom are over .500 themselves. So is this a case of legitimate improvement or of a given sample belying the truth?

For the month of April, Cubs relievers posted a 3.38 ERA and .228 BAA, 18th and 20th in MLB respectively. And even including the last week of May that begins Muskat’s mention, that same unit put up a 4.37 ERA (24th) and .246 BAA (20th) on the month.

So far in June, however, they’ve managed a 1.39 ERA and .193 BAA, both 5th in the majors. Pretty sexy numbers, huh? I wanted to believe that this was a positive regression for the relievers and not just a couple of retouched Glamour Shots taken in soft focus to hide the truth.

After all, using stats like ERA and batting average can be pretty deceiving, particularly in a small sample size. So the first place I went looking was in the relief corps’ FIP and xFIP during the various months of the season thus far. Without getting into the full definition, those two stats are more accurate measures of pitchers’ efficacy.

As you might imagine, May was the worst. The unit in question put up a 4.54 FIP (27th) and 4.12 xFIP (25th), pretty well in keeping with their ERA performance. April was actually really good though, as the Cubs put up a 2.81 FIP and 3.27 xFIP, both good for 6th in MLB. So one unlucky month and another in which they were flat-out bad; nothing conclusive.

So far in June, the relievers’ 2.61 FIP is again 6th in the majors, but their 3.73 xFIP is 18th. Again, we’re left with some pretty inconclusive stuff here. But that big gap here in June got me thinking; xFIP is a regressed version of FIP that accounts for how many home runs a pitcher should have allowed. So is the discrepancy here an indication that the Cubs have been getting a little lucky?

For that, I looked to BABIP against for each month in the season. As a quick tutorial, Batting Average on Balls In Play measures how often a struck ball lands for a hit. With league average typically falling around .300, we can typically attribute deviations on either side of that mark as being due to either good or bad luck.

In Apri and May, Cubs relievers surrendered respective BABIP against totals of .292 and .295, just slightly better than the league averages of .294 and .296 for those months. Really not enough deviation there to say that the relievers were benefiting in any significant way from good fortune.

In June, however, that BABIP against number has dropped to .239, third-lowest in the majors on the month. At the same time, the league average for hitters this month sits at .303, a high-water mark for the season. If my rudimentary grasp of basic math is correct, that’s a 64-point gap between the two numbers and a sign of some very serious good luck for the Cubs.

Maybe it really is better to be lucky than good. Even so, I wasn’t ready to simply define the Cubs with a dirty fortune cookie message reading #thebullpenislucky.

Still unprepared to make a solid pronouncement, I wanted to look at one more set of stats: K% and BB%. While the Cubs relievers have been striking out a smaller percentage of batters each month — from 24.2 (11th) in April to 21.2 (17th) in May to 20.7 (19th) in May — the walks have been very inconsistent (big surprise).

In April, Cubs relievers walked 6.8% of the hitters they faced, good for 4th in MLB. In May, however, that total was up to 11.9%, dead last in baseball. It goes without saying that walks are the bane of a reliever’s existence, so we can see yet again why May was such a rough month for this group. A week and a half into June, they’re down to 5.8%, 6th in MLB.

At the risk of closing with a complete cop-out, I can only say that this unit of relief pitchers is neither as bad as what we saw in May nor as good as what we see in Carrie Muskat’s tweet. But you know what? Just replicating April over and over would be fine. They were 12-8 during that first month of the season before playing .500 baseball in May.

Going 4 games over for the months of June, July, August, and September before closing out with a little run in the first 4 days of October would put the Cubs just under 90 wins. We’ll probably see a little regression from the pen over the next few weeks, but that’s not an entirely bad thing. Of course, the bats will have to pick up the slack.

After all, you can’t rely on this run of luck to hold out. Then again, I’ve long lived under the concept that luck is what happens when preparation meets opportunity. The Cubs have an opportunity to be a really good team and they’ve begun to prepare for a meaningful stretch run with the addition of Rafael Soriano and the potential for a Jonathan Papelbon deal.

With the return of Neil Ramirez — which remains shrouded in mystery — there’s potential for things to really solidify in the pen. Then you look at removing guys like Edwin Jackson and Travis Wood, who, despite some decent performances here and there, have defined inconsistency with their performance.

At the end of the day, it’s solidarity that they need back there; Joe Maddon needs to know who he can trust to take the bump as the season moves on. And I think the Cubs can get there. So yeah, it’s not great, but the #thebullpenisgood and could be getting much better.