I’m Walkin’ Here: A Bullpen Story

The Cubs bullpen, by and large, has been good, as it was expected to be. Overall, the bullpen sports an impressive 4.01 DRA, good for fourth in the majors, whereas the starters rank 14th with a 4.86. On the more traditional side, the relievers have fared just as well, with a 3.45 ERA that ranks fifth, immediately behind the Yankees and one large gulf behind the super ‘pens in Los Angeles, Boston, and Cleveland. The bullpen is fourth in leaving runners on base, fifth in strikeout rate, third in opponent batting average, and even second in BABIP due to a quality defensive unit. In nearly every aspect, the arms who hang out under the left-field bleachers have acquitted themselves well, and have helped mitigate poor or injury-rattled seasons from the rotation.

Recently, however, the group has done little to inspire confidence. In the last month, the bullpen has been middling in many of the same categories in which they have appeared excellent over the course of the season, and in one category conspicuously missing from the above list of accolades, they’ve been the worst in the majors. Over the last 30 days, the bullpen has managed to walk an untenable 12.6 percent of hitters, even worse than their 11.0 percent season mark, worse than only the Brewers. Overall, walks have torpedoed an otherwise effective relief unit, sinking WHIPs and blowing up games in the late innings that should have been converted into victories.

This is a rather obvious conclusion, though—anyone with a few minutes and a computer can pull up the leaderboards and find these numbers—and looking at the bullpen holistically can only tell us certain things. Picking apart a few relievers’ seasons, with particular attention to their walk rates, will provide us with some insight into how this group works as a unit, and how they might be better deployed individually and in concert with the other relievers. And so…

Wade Davis 38.0 33.3 12.0 .194 46.9 2.37 2.29
Koji Uehara 38.0 29.2 6.5 .208 40.0 3.32 4.51
Carl Edwards, Jr. 44.2 35.0 16.4 .139 54.1 3.83 2.72
Pedro Strop 41.0 27.1 10.6 .188 39.5 2.41 2.87
Hector Rondon 43.1 30.1 9.7 .215 42.6 3.95 3.35
Brian Duensing 46.1 28.2 5.3 .222 35.6 2.33 3.53
Mike Montgomery 46.2 18.5 13.3 .211 34.4 2.51 4.98
Justin Grimm 40.0 25.5 12.1 .215 43.0 5.18 4.65
Justin Wilson 43.1 33.3 10.9 .168 47.1 2.70 3.15

Notes: Montgomery’s stats are as a reliever. Wilson’s stats are for Detroit and Chicago combined. TTO% is the percentage of batters faced with the result being one of the three true outcomes.

A few things stand out immediately.

  1. Hector Rondon is still quite good and should probably be given higher leverage situations, considering his relatively reasonable walk rate.
  2. Brian Duensing has been an ace LOOGY who has walked no one.
  3. The bullpen strikes out a helluva lot of hitters.
  4. The bullpen doesn’t allow many hits.

In a game trending toward full dominance of the three true outcomes (walks, strikeouts, home runs), the Cubs bullpen is one of the most radically constituted cadres of relievers in the league. Rarely will they give up a hit—these pitchers’ opponents end the at bat with either a walk, strikeout, or homer about 35 to 50 percent of the time, with Carl Edwards, Jr. leading the pack. That can be a generally useful trait, especially when entering the game with runners on base, and walks are slightly more desirable in most situations than hits, but there have been many times this season when a Cubs’ reliever simply cannot find the strike zone and subsequently imperils a lead. Overall, the ‘pen’s 11.0 walk percentage is 2.5 points higher than the league average this season, and only Uehara and Duensing come in under the 8.5 percent mark.

These performances aren’t static or stable, though, and several relievers have performed either better or worse over the past few weeks than their overall numbers let on. Primarily, Edwards has struggled since the All-Star break, to the tune of 11 walks in 9 ⅓ innings with ten runs allowed. In his last three appearances, he’s given up two runs, one run, and four runs. Joe Maddon has given Edwards a breather to regain his command and composure before throwing the skinny righty back into the fray, but it’s not a foregone conclusion that Edwards will return to the generally excellent form in which he had been most of the season. It’s time to be cautious with him, especially considering the performances of Rondon and Strop.

About those two: they’ve been very good! After a tough stretch late last summer and into the fall following an injury and the acquisition of Aroldis Chapman, Rondon has bounced back to become a reliable bullpen arm once again. The former closer hasn’t allowed a home run since June 14th, and he’s turning 51.4 percent of batted balls into grounders on the year. In fact, since the All-Star break, Rondon has only allowed a run in one appearance (an admittedly disastrous outing versus St. Louis in which he allowed four runs and secured no outs). But Rondon has been trusted with situations much less important than those with which Edwards has been trusted: Rondon’s gLI (leverage index when entering a game, where 1.0 is average) for 2017 is a mere 0.96, while Edwards has handled the tense scenarios and entered, on average, with a leverage index of 1.33. Rondon has been handed a few higher leverage innings since the break, but Edwards has still been Maddon’s favorite fireman.

Even better than Rondon has been his long-time late inning companion, Strop. Not a runner has crossed the plate on Strop’s watch in 8 ⅔ innings since the All-Star break, and he’s allowed a lone hit over that period. The slider-dealing righty has induced a remarkable 67.6 groundballs on balls in play this season, and Maddon has handed Strop similarly high leverage situations (1.31 gLI) as he has with Edwards, a higher mark than last year. As such, it would be difficult to hand Strop any more key innings than Maddon already has.

Rounding out the back end of the bullpen is Uehara, who has walked very few hitters this year and struck out almost 30 percent of batters faced. He’s in the same tier of gLI as Edwards and Strop, as he’s often been trusted with bridging the eighth inning to get to Davis, but Uehara has dealt with a rash of home runs lately. Using our All-Star break cutoff, Uehara has surrendered four homers in just 8 ⅓ innings, striking out 13 and walking none. This suggests either a fluke or a quality of contact/batted ball problem, and, given Uehara’s age and velocity, I am inclined to believe the latter is true. DRA is not kind to the 42-year-old, and his batted ball profile—only 26.8 percent grounders, compared to 24.7 percent line drives and 48.5 percent flyballs—are all significantly worse than league average this season. Of course, Uehara lives on finding strikeouts with his splitter and suppressing walks with good command. Uehara is the most enigmatic of these pitchers due to his unique profile and ability to find success in more unorthodox ways and at an advanced age.

Handing more stressful innings to Strop, Rondon, and the newly acquired Justin Wilson while eschewing usage of Edwards and Uehara, at least for a brief period, could pay off for Maddon and the Cubs. Having the young Edwards and aging Uehara fresh for the playoffs would be an added benefit, and knowing if Rondon can be trusted with a playoff game on the line could assuage Maddon’s doubts. And Maddon appears to have a plan for Edwards; it’s not the old manager’s first time managing a struggling reliever.

Usage is not merely the domain of choosing which relievers to insert in specific situations, though. The command problems that have plagued the ‘pen are compounded by the fact that the Cubs use their bullpen considerably more often than other teams with elite relief corps. Maddon has been quick to pull his starters this season, often for good reason, but his decisions have resulted in more work from the fifth inning onward being taken on by the walk-happy bullpen. The Cubs bullpen has thrown the eighth-most innings in the majors, and starters are only turning in quality starts 44 percent of the time, right in the middle of the pack among all major-league teams. To put it in perspective: Cubs starters have tossed 610 innings and walked 205 batters; relievers have pitched 383 innings and walked 175.

If Cubs relievers can somehow walk fewer batters and remain effective in limiting hits and hard contact—or, if Maddon can deploy more often the pitchers less likely to walk hitters—the bullpen might find a bit more success, and the ends of games won’t be the tense affairs brought on by command issues that they are now.

Lead photo courtesy Dennis Wierzbicki—USA Today Sports

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