MLB: Los Angeles Angels at Chicago White Sox

Wait, The White Sox Bullpen is How Good?

The White Sox currently have the best bullpen in Major League Baseball.

If you’re anything like me, that statement may have caught you off guard just a bit. But it’s not as if it’s completely unfounded. The pieces have always been in place for this bullpen to be great. One might even suggest that the bullpen was one of the strongest areas of improvement in GM Rick Hahn’s epic rebuild during the 2015 offseason.

Through April in 2015, (only fair when comparing to the success the 2016 bullpen has enjoyed) the White Sox had the sixth best bullpen ERA in all of baseball (2.91). This pen also had the fourth best FIP (their FIP beat their ERA by a small margin at 2.81) and struck out 9.05 batters per nine innings.

That’s nothing to flinch at, and if the 2016 bullpen was producing those same numbers, I would hardly be complaining. But the quality of this bullpen was somewhat negated last season by the the April 2015 White Sox team going 8-11, and its run differential of -25. It’s hard to praise a bullpen for doing its job effectively when the run support isn’t there.

But let’s fast forward back to the present. The 2016 White Sox are currently 19-9, are leading the AL Central by four games, and are among the top three teams in baseball. We’ve seen great teams rack up the offensive numbers and dole out superb starting pitching in the past, and we’ve also seen these teams have their success undone rather quickly at the hands of insufficient bullpens. The importance of bullpen production to sustain the success this club is seeing so far in 2016 is very real.

Everything seems to be working in concert for the White Sox right now. Stellar pitching has quieted opposition run totals to the point of a +25 run differential, instead of last season’s -25. The offense, though Jose Abreu and Todd Frazier were off to slower than expected starts, has consistently delivered whether it be via vital new roster pieces like Brett Lawrie, or surprising bench options like Jerry Sands. But perhaps most importantly, tying it all together, is the bullpen.

So we know the ‘pen is good, but let’s break down just how good it is compared to the rest of the league:

Stat Total MLB Rank
ERA 1.75 1st
FIP 2.68 2nd
WAR 1.6 2nd
GB% 50.7% 4th
FB% 29.6% 2nd
BAA .199 3rd
HR/9 .23 1st
HR/FB 3.3% 1st
LOB% 81.1% 6th*
K% 23% 13th
BB% 7.9% 10th

*The White Sox are .1% below the 4th place team in LOB% with two teams tied for 5th, and before Wednesday’s game were 3rd in LOB%. 

Considering that most of these numbers rank first through third place out of all 30 teams, this is quite impressive, and there are certainly more top tier totals than I expected to find. The Sox bullpen may not have a top three strikeout rate, but their ground ball rate is elite, true to philosophy as conveyed by pitching coach Don Cooper during SoxFest, “Listen, if you’re not getting groundballs, you better get strikeouts.”

The impressive ground ball rate has led to, or perhaps is the result of, the White Sox bullpen’s 26.6 percent soft contact rate, the highest in all of baseball, which also accompanies the fifth lowest hard contact rate at 24.6 percent.

Having the second lowest fly ball rate in the majors is reassuring as well, seeing as U.S. Cellular Field is known as a hitter friendly ballpark. Even when the ball is being been hit in the air — they’re keeping it in the yard. The White Sox bullpen has only allowed two home runs this year, the fewest in baseball, translating to the lowest HR/FB% by nearly two percentage points.

They may not be leading the league in strikeout rate, but the White Sox are just above middle of the pack, and as long as they continue limiting the hard contact while inducing ground balls at a high rate, they’ll continue to have great success. Their walk rate is tenth in baseball, but still below league average and in the top third percentile. Overall, the biggest comfort in these numbers is that the fly ball rate is low, the hard contact rate is low, and that this bullpen is keeping the home run totals to a minimum.

Now let’s take a look at how they’re achieving all of this by examining the success of the individual contributors:

Player IP ERA BB% K% GB% FB%
Matt Albers 12.2 0.00 6.7 17.8 48.4 32.3
D. Robertson 12.1 0.73 8.9 33.3 53.8 30.8
Nate Jones 12.0 0.75 4.6 22.7 33.3 43.3
Zach Duke 11.0 2.45 4.4 20.0 60.6 18.2
Zach Putnam 10.0 4.50 5.0 27.5 40.7 37.0
Dan Jennings 9.0 1.00 0.0 18.9 51.7 27.6
Jake Petricka 8.0 4.50 20.5 18.0 69.6 21.7

Certainly the most impressive of the group has been the re-emergence of Matt Albers, who has absolutely dominated and pitched the most innings out of the bullpen to date, all without being charged with a run — a streak dating back to August of 2015. Albers’ heavy ground ball rate is a result of him using his sinker with 76 percent frequency in 2016. When he’s not throwing it for a strike, he’s inducing contact on it for outs — simple as that.

The biggest key for this group of relievers, which I cannot stress enough, is how well they’re doing with keeping the ball on the ground and minimizing fly ball outs that could lead to trouble. Only Zach Putnam and Nate Jones are currently posting fly ball rates above or close to their ground ball rates. Nate Jones’ fly ball rate could become a concern if he doesn’t ramp up his strikeout production, as it’s the majority of the way he gets his outs on balls in play right now, an approach that could easily become dangerous when the nights get warmer and the winds pick up. But for right now, Jones has looked like the reliever the Sox have sorely missed.

It feels as though there’s a sense of order in this bullpen each night. Everyone has a specific role that they fit into, and the tandem of Zach Putnam, Jake Petricka, and Dan Jennings, all leading up to either David Robertson, Nate Jones, or Matt Albers has been a consistent success.

This doesn’t look to be some sort of luck that will fade as the season progresses, these numbers aren’t completely propped up with outliers that are due for regression with the exception of Albers’ ERA — unfortunately, that train ride has to end somewhere. This bullpen is looking like the real deal, as is the entire White Sox ball club in 2016.

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4 comments on “Wait, The White Sox Bullpen is How Good?”


loved the Robertson signing last year. it’s a lot easier shuffling other pieces around when you don’t have to worry about the 9th inning.

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