The Cubs’ Rotation Got Fixed

On July 20th, my colleague Craig Edwards wrote a piece for this site entitled “The Cubs Are on Pace for Their Worst Rotation Ever” in which he argued — in accordance with all observable objective reality at the time — that the Cubs were on pace for their worst rotation ever. It wasn’t an especially difficult case to make. At the time Craig published, the Cubs’ rotation — which still featured rather too much of Tyler Chatwood — had produced just 3.0 WAR as a group, which is the kind of figure that, as a measure of collective performance through nearly three months of a major-league season, is apt to make one physically recoil regardless of how you feel about pitcher WAR’s usefulness as a measure of overall performance. It was bad.

Since then, however, the Cubs’ rotation has been rather good, and that fact is the point of this article. Consider the following table, which presents the Cubs’ rotational performance up to and including the 20th of July, and also after that date (MLB ranks in parentheses):

Cubs’ Rotation Performance Pre- and Post-Craig Edwards Post
Period IP K% BB% ERA FIP xFIP
Pre-Craig 510.2 (25) 19.6% (21) 10.8% (30) 4.02 (12) 4.75 (25) 4.58 (24)
Post-Craig 295.2 (10) 21.8% (15) 8.0% (22) 3.65 (10) 3.67 (9) 3.92 (12)

You will agree, I hope, that the Cubs’ rotation has been better since Craig said they were bad, and will therefore turn your attention with me to why. Here is one reason: it has much less Tyler Chatwood in it. Here is another: it has much more Cole Hamels. These might sound like blithe (and, in Chatwood’s case, rather mean) things to say, and to some extent they are. But they are also true.

Chatwood, who the Cubs signed to a three-year deal this offseason and was described as “excited to pitch at Wrigley” Field shortly thereafter, was terrible in the 17 starts he took before the 20th, walking an astonishing 18.6% of the batters he faced in 84 mostly dismal innings. Chatwood unambiguously has the stuff necessary to being a good big-league pitcher, so it’s not entirely clear what was going on. Whatever it was, though, it wasn’t good. He’s made just seven appearances since Craig published, four in relief. Replacing his performance with the work of other, more capable pitchers has gone a long way towards righting the Cubs’ ship.

With Chatwood clearly out of the organization’s good graces by the early summer and Yu Darvish well on his way to the diagnosis that would eventually end his season, the Cubs needed another man for their rotation, and they found him on July 27th in the person of Cole Hamels. Hamels had been positively Chatwood-like in his last dozen or so starts in Texas — he recorded a 5.74 ERA in his final 11 starts before the trade, an 11.12 over his last four — but the Cubs saw something they liked in his delivery and picked him up for Eddie Butler and change. They even got Texas to throw in some cash in the deal, putting them on their way to avoiding MLB’s luxury tax for yet another year.

The rich always get richer. Hamels has been dominant as a Cub, striking out 55 and walking just 19 in his first nine starts with Chicago. His ERA since the trade is 1.57, and his handsomeness still rates a 10 out of 10. Since arriving on the North Side, he’s become a far more pronounced four-seam fastball pitcher than he’s been since his days with the Phillies in the last part of the 2000s, ditching the cutter along the way, and he’s paired that simplified approach with a few extra ticks of velocity that can be hard to come by at 34 years old, but which make all the difference in the world for just that same reason. The Cubs needed someone, anyone, to step into their rotation and stabilize it, and they got that and more in Hamels. That’s a winning lottery ticket.

Far more predictable was the modest improvement, from a high baseline, of Jon LesterJosé Quintana, and Kyle Hendricks. As Craig noted in his piece, the early-season Cubs were actually fairly decent at preventing runs, despite their low WAR totals, and Lester and Hendricks in particular were running somewhat ahead of their projections for ERA even as their FIP ran somewhat behind expectations. Quintana, who’s battled some inconsistency since arriving on the North Side a year ago, was running slightly behind his projections, but even his performance through that point was perfectly acceptable. It was Chatwood and Darvish who were holding the Cubs back. With Hamels in the picture and those three men out, even modest improvement by the three holdovers (Lester, Quintana, and Hendricks) would contribute to a picture of dramatic improvement. And that’s exactly what we’ve seen.

Sometimes baseball is complicated, sometimes it’s not. When Craig wrote his piece, the Cubs had three decent starting pitchers, one injured one, and one bad one. They replaced the bad one with a great one, found a few Alec Millses and Mike Montgomerys to fill in the gaps for the injured one, and watched their three decent pitchers turn into the good ones they’d been before and will likely be for some time to come. Craig took you on a tour of the Cubs’ rotation at the bottom of their valley. It’s been all uphill since then, with new faces and new energy carrying the Cubs to the place we always expected their rotation to end up. The Cubs will probably end up in the postseason in a few weeks despite a struggling offense and a bullpen held together by papier-mâché. They will not, at the very least, have to worry overmuch about their starting pitchers.





Rian Watt is a contributor to FanGraphs based in Seattle. His work has appeared at Vice, Baseball Prospectus, The Athletic, FiveThirtyEight, and some other places too. By day, he works with communities around the world to end homelessness.

11 Comments
Oldest
Newest Most Voted
Inline Feedbacks
View all comments
Psychic... Powerless...
5 years ago

So none of the Cubs starting pitchers can ever become a father? Interesting decision by Theo.

Brewtown_Kev
5 years ago

He doesn’t want them to have tired legs.