On May 15, with the Cubs sitting at 27-9, CBS Sports.com splashed around words such as “historic,” “remarkable,” and “incredible” in describing the team’s start.
On June 7, with the Cubs having advanced their record to 40-16 the night before, FiveThirtyEight made the stunning comparison of Maddon’s bunch to the 1927 Yankees.
Now, as the season resumes Friday after the All-Star Break, the Northsiders are 53-35. The team’s record has been 26-26 since the CBS Sports article and 13-19 since FiveThirtyEight’s piece.
The Cubs’ slide began on June 20, the opening day of a three-game Wrigley Field series with St. Louis, which the Cardinals swept. Chicago has now lost five of its last six series (plus a one-game make-up game with Atlanta). Using the Cubs’ game-by-game log, I plotted the results of all of their series so far this season, in chronological order. Opponents are shown on the horizontal axis and the outcome of each series is shown on the vertical axis (sweeping a three-game series would be +3, getting swept four would be -4, etc.; see legend below the graph). You may click on the graphics to enlarge them.
Presumably, the Cubs have declined in one or more of the following areas: hitting, pitching, and defense. Hitting does not seem to be the major problem. The team’s two leaders in OPS (On-base Plus Slugging percentages), Anthony Rizzo and Kris Bryant, have maintained a torrid pace. In fact, Rizzo’s two best monthly OPS figures have come in June (1.211) and July (1.178). The same is true for Bryant (June, 1.058; July, 1.222). Addison Russell and Jason Heyward have been steady, if unspectacular, with monthly OPS values in the .700-.800 range of late. That’s not to say that nobody has slumped. Dexter Fowler’s OPS in April, May, and June fell respectively from 1.087 to .879 to .605, and Ben Zobrist has fallen to an OPS of .707 in June and .640 in July, after he had attained a 1.136 in May. Still, there is no universal collapse in hitting among the Cubs.
To evaluate starting pitchers’ individual outings, I use the “game score” statistic developed by Bill James. The scoring system starts a pitcher out with 50 points, then adds points for good pitcher outcomes (e.g., 1 point for each out, plus an additional point for a strikeout) and subtracts points for bad outcomes (-2 for each hit allowed, -4 for each earned-run yielded). Game scores for each and every start by a given pitcher are included among ESPN.com’s pitching statistics. I have plotted game scores for each of the Cubs’ five regular starters, shown in chronological order.
Although the data are noisy, the general trend is that Cubs starters – four of whom are age 30 and older – began declining around their 15th starts. Before that, most outings were in the 50-80 range (highlighted in gray), meaning that pitchers made a net gain in points above the 50 with which they automatically started.
John Lackey recorded a 23 in his 15th start (a 9-6 Cubs loss at Miami), Jason Hammel struggled badly with a 5 in his 16th start (a 10-2 loss at the Mets), and Jon Lester also registered a 5; this came in his 17th start, another blow-out loss (14-3) at Citi Field. Jake Arrieta, though not hitting the low points of some of his teammates, has thrown clearly subpar games in his last three starts (game scores of 38, 38, and 35). Kyle Hendricks has been the even-keel starter, never deviating from a range of 41-80.
According to another FiveThirtyEight article, as of June 19 (right before the Cubs’ spate of losing series), Chicago pitchers appeared to be benefiting from two developments: their “contact-management skills” or “tendency to allow batted balls that do less damage;” and excellent defensive play from the fielders. Getting into the physics of batted balls, “Cubs pitchers [had] depressed exit velocity by 0.4 miles per hour and launch angle by almost 2 degrees, relative to average.” In terms of fielding, free-agent acquisition Heyward has saved 35 runs with his defense in 2015 and 2016 combined, according to one estimate, which is one of the best performances for an outfielder during this time.
One would guess Cub pitchers lately were allowing balls to leave opposing bats with greater exit velocity and launch angle, although I do not have updated statistics on those parameters. The Cubs need some rest, according to Maddon. That’s as good a recommendation as any, especially for the starting pitchers.