Should We Be Worried That Craig Counsell Couldn't Fix the Cubs' Run Differential Problem?

To a point, it feels like the 2024 season was almost the exact same story as the 2023 season for the Chicago Cubs. A good April gave way to a very poor May and June. The team clawed back into the Wild Card race with a good July and August, but ultimately ran out of steam in September to miss the playoffs.

There was an offense that didn’t hit a lot of home runs, and a pitching staff that was above-average, but plagued by bullpen issues just when they could least afford them. There is one more parallel between the 2023 and 2024 seasons that I feel has flown under the radar a bit: run differential. For the second season in a row, the Cubs are set to underperform their expected record, based on runs scored and allowed, by several games. 

Last year, the Cubs outscored their opponents by 96 runs. That was more than the Milwaukee Brewers, who won the division, and more than all three of the teams who made the playoffs ahead of them via the Wild Card. From that run differential, they had an expected record of 90-72, seven games better than the 83-79 record with which they actually finished.

This year, it’s not quite as dramatic. The Cubs have outscored their opponents by 67 runs. That gives them an expected record of 85-71, which is five games better than their actual record of 80-76.

To be clear, the disparity this season is a bit less frustrating, considering the circumstances. The Brewers, as well as all four teams ahead of them in the Wild Card race, have a better run differential. Playing to their run differential would still not have made them a playoff team this year, or at least, it would still only have them scrambling to make up multiple games over the final week.

Regardless, this is a trend worth examining. Run differential, while not the end-all, be-all of team quality, can be one of many ways to determine if a team is overachieving or underachieving. This is due to the amount of statistical noise present in a one- or even two-run win--or loss. One really good performance from one player can swing those games. Winning games by four, five, or six runs requires several of those performances, which is where truly elite teams separate themselves from the pack.

When discussing run differential, there are three reasons usually given for why a team might overperform or underperform. One is strategic decisions. The Cubs fired David Ross after last year and replaced him with Craig Counsell, who was thought of as one of the best managers in baseball and whose Brewers teams had a history of overperforming their run differentials. Despite this, the Cubs saw no improvement in this area, so I am going to rule this one out, though I do think it begs for a larger discussion over the role a manager has, both in this area and in general.

Second would be the bullpen. Believe it or not, the Cubs actually have the 11th-best bullpen ERA in baseball over the past two seasons, according to FanGraphs. They have a better bullpen ERA this season than the Phillies, Diamondbacks, and Orioles, who will all be playing baseball in October, and who are all within two games of their expected record this season. This is not a strength for the Cubs, but over the course of two entire seasons, it has not been a weakness, either.

The third reason would be clutch performance. On offense, the Cubs have hovered around the same wRC+ in high-, medium-, and low-leverage situations. Pitching, on the other hand, is a different story:

Wow! Cubs pitchers have been considerably worse in high-leverage situations than in low-leverage situations over the past two seasons. It’s kind of weird that this has happened twice, right? If you’re wondering whether or not this is a league-wide trend, it isn’t: per FanGraphs, MLB as a whole posts its lowest wOBA in high-leverage situations. That makes sense. Most of the time, teams use their best pitchers in those spots, to whatever extent they can do so.

All of the potential reasons for this type of phenomenon would require another full article. I consider myself to be a pretty practical person. Most studies have shown that the ability to perform in clutch situations isn’t really a thing, so I am unlikely to chalk this up to Cubs’ pitchers lacking some kind of “it” factor. The staff as a whole allowed a .303 wOBA in all situations this year, so I am inclined to believe that if we up this sample size, the wOBA allowed in high, medium, and low leverage situations would all end up at about .303. In the same way that if I flip a coin 10 times and they all land on heads, the odds of my next flip being tails is still 50 percent, I believe this will regress toward normalcy in the future.

But, still. It is really weird that this has happened twice. I’ll still say that I think this is most likely luck. However, I do wonder if this tells us something about the Cubs’ lack of top-flight arms. They've lacked the kind of shutdown arms other teams deploy in those big spots, at least for stretches of the last two years. The signal amid the noise here is saying: Invest in more certainty in the bullpen, one way or another.