Second City October: Keeping an Eye on the Cubs ‘Pen

This piece, written by BP Wrigleyville’s Cat Garcia, forms part of our in-house coverage of the Cubs in the playoffs, “Second City October”.

The outcome has been decided. The Cubs won’t enjoy vengeful rematch with the Mets this weekend at Wrigley Field. Instead, they’ll be facing the San Francisco Giants. The wave of apprehension that blanketed the Cubs fanbase upon this realization was a bit abrupt, as most fans seemed to have prepared more extensively for the idea of a possible Mets rematch. But once that possibility was eliminated, a slight wave of apprehension came over the North side. The Cubs now have to face Madison Bumgarner and his San Francisco Giants crew.

However, the Cubs still have nothing truly to fear. They may have been matched with the stronger of the two possible opponents thanks to a storybook postseason moment for Conor Gillaspie, but no matter how you roll the dice, the Cubs are still the better team by ERA, DRA, average, on-base percentage, and slugging percentage. The only question, really, is the bullpen.

Bullpens are always the most questionable aspect of any playoff game. They leave managers, organizations, and fan bases with so many questions from day to day, even moment to moment. Of course in the playoffs, knowing when to flip the switch from starter to relief crew can be a difficult song and dance. Which will be the lesser of the two evils? Will there be a game seven?

The good thing is, the Cubs have the stronger bullpen of this matchup, too. The Cubs currently have the 8th best bullpen in baseball by ERA, which may not bode extremely well since there are a few other playoff teams ranked above them, but for right now they have the advantage. The Giants currently own the 15th best bullpen in baseball by ERA. That is quite the disparity.

FIP is the area of concern for the Cubs. The Cubs bullpen ranks 14th in FIP at 3.87, while the Giants rank 11th at 3.78.

We know what the reason is for this though. It’s been alluded to and even point blank talked about all season—the Cubs have good defense. Their defense has helped not only the rotation this season, but it’s also aided a bullpen that has a 47.5 percent groundball rate.

One of the main concerns for the Cubs bullpen this season has been home runs. The Cubs relief crew holds the 3rd worst HR/FB rate in baseball, at 14.2 percent. Keeping the ball on the ground as much as possible for a team with such recognizably strong defense will be key during the playoffs.

But another small but meaningful aspect to recognize about this Cubs ‘pen is that thanks to the performances we’ve seen from the Cubs starting rotation this season, who have pitched the second most innings in baseball behind the Toronto Blue Jays, this bullpen is very rested. So well rested in fact, that they have the fourth-fewest innings pitched among all bullpens this season, and would be tied for third if not for a pesky ⅓ of an inning that separates them from the the Red Sox.

Something that will certainly be kept under the watchful eye of Joe Maddon is the performance of setup men Pedro Strop and Hector Rondon, both of whom were sidelined for weeks during August and part of September. Let’s check out their numbers since both of their first games back in action (9/6 for Rondon and 9/23 for Strop):

IP ERA FIP ER BB K HR Opposing Hitters
Rondon 7.1 9.82 6.01 8 2 7 2 .394/.444/.697
Strop 3.2 2.45 3.42 1 2 4 0 .091/.286/.273

Of course, these numbers should most certainly be taken with a grain of salt, as the sample sizes are so small. This is mainly why I included the raw totals instead of things such as walk or strikeout percentage, home run rates, etc. which in a small sample size can be drastically misleading (Strop’s 14.3 percent walk rate looks much less alarming when presented as “Strop has walked 2 batters in 3 2/3 innings of work”).

It’s apparent that Rondon has struggled a bit more since his return, as he’s allowed two home runs, and struck out batters at a lesser rate than Strop has. Rondon has also allowed more than one run per inning of work which is evident in his slash line against. Strop seems to be making a smoother transition back to the mound, however, free bases have much more significance in the small sample size confines of October.

Thankfully, Maddon has been ready for any outcome October has to offer. He has newcomers Rob Zastryzny and Mike Montgomery stretched out and ready to go in case any sort of issue arises, anything from poor performance to a sudden injury. Maddon also has the ability to deploy familiar arms such as Justin Grimm, Travis Wood, or Carl Edwards Jr, all of whom will be on the postseason roster along with fireball throwing Aroldis Chapman. The Giants don’t have him, and neither do any of the other teams that Cubs will face this October.

One series at a time, Northsiders, and for now, the Cubs have themselves figured out for this one. They have the advantage, they just need the mind set and the drive. This may be the tougher of the two possible options the Cubs had before them, but the difference is relatively minor.

Lead photo courtesy Jerry Lai—USA Today Sports.

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