Cubs Define Bullpen Roles, Turn Biggest Weakness Into Strength

The Chicago Cubs' approach to building a bullpen isn't a secret. Nor is it uncommon. There's no secret sauce. Unfortunately, though, the throwing-upside-at-the-wall-and-seeing-what-sticks approach does take a little while to brew. In their case, it took virtually all of March and April. 

By ERA, the Cubs had the 26th-ranked bullpen in the season's opening month and change (4.76). They were 27th in strikeout rate (19.2 percent), 26th in walk rate (11.8 percent), and 24th in strand rate (66.0 percent). While they were able to limit quality contact — their 35.6 Hard-Hit% was fifth-best — there was simply too much traffic for even a somewhat modest .294 BABIP to not bite them in the way that it did. 

As is expected with that type of performance, we lost some friends along the way. Nate Pearson pitched to a 10.38 ERA across 8 2/3 innings and was optioned to Iowa by the middle of the month. Eli Morgan posted an even higher mark before an elbow impingement sent him to the injured list, where he still resides indefinitely. While a different context entirely, Colin Rea wasn't long for relief work, as injuries in the rotation forced him into a starting role. And that's just in the middle of the 'pen.

The responsibility of finishing games that were otherwise propped up by one of the league's top offenses was a burden. The Cubs blew seven saves during the first month of the year. Interestingly, none of them were from Ryan Pressly, whose 2.25 ERA covered for brutal peripherals (a 5.09 FIP & a walk rate that exceeded a floundering strikeout number). It was a harbinger of things to come, as the veteran righty lost his job in the month that followed. 

Ultimately, the March & April group was a hodgepodge of veteran (as in, some of these guys are old) arms attempting to navigate low power and heavy traffic. Even as the Cubs at large held together against a brutal schedule, the bullpen was the part of the roster that was clearly the weakest... until that calendar read "May 1", at least. 

Last month was a different story entirely for relievers on the North Side. Their 2.37 collective ERA was the best in all of baseball. The walk rate climbed all the way to seventh (8.3 percent), and the strand rate took over the top slot (78.9 percent). While they still weren't posting gaudy punchout numbers (21.8 percent), the BABIP fell to .261. Most essential within the strong output is that a clear core of the '25 bullpen started to take shape. 

Each of Caleb Thielbar (8.0 innings), Drew Pomeranz (9 1/3 innings), Brad Keller (14 2/3 innings) blanked the opposition with perfect 0.00 ERA marks. Chris Flexen was able to accomplish the same task in a largely multi-inning role (14 1/3 innings in eight appearances), as was Ryan Brasier (albeit in much more limited work in his 3 1/3 innings off the IL).

Perhaps the most important development for the group, though, came in the form of Daniel Palencia as the team's primary ninth inning option. With Porter Hodge suffering an oblique injury, the team's most electric arm was pressed into the closer role and absolutely delivered. Through an even dozen innings of work, he posted a 1.50 ERA and five saves. Even with one blip in Miami, the emergence of his 98th percentile fastball velocity appears to have settled the most pressing issue in the 'pen.

Rather than work with the least bad (or, at best, questionable) option, Craig Counsell was able to operate with a little bit of freedom in turning to those presenting actual efficiency in their appearances. As such, Pressly's tightrope act was relegated to garbage time, while Julian Merryweather's velocity decline cost him a role via mid-month DFA. So, it's no wonder that certain elements that we saw escape the team's ability to navigate the middle and late innings became much more settled last month. 

That's primarily reflected in strike one. The Cubs ranked 22nd in first-strike percentage in March/April, at 59.1 percent. Subsequently, opposing hitters were only swinging at a 45.1 percent clip (also 22nd) and chasing only 31.8 percent of the time (13th). The whiff rate sat at just 9.8 percent (27th). In May, though, that first strike figure shot up to 66.5 percent (1st). Along with it came the swing rate, at 48.2 percent (7th). By forcing hitters into swings that they may be otherwise unwilling to make, you're putting the ball into the hands of your defense (given the still-relative absence of overall strikeout stuff). When you do that, rather than take the ball out of their hands entirely through the death knell of any bullpen (read: walks), you're going to find more consistent and sustainable success. That's what we saw in May. 

Ideally, that's what we'll continue to see. It's not always going to be as sterling as it was last month (especially as temperatures heat up). But, there are clearly some reliable options that have emerged for Counsell to circulate as the rotation gets healthier (Shota Imanaga) and more consistent (Ben Brown).

It wasn't pretty — working through the ugliness in the early going and letting "your guys" settle in rarely is — but the Cubs' bullpen appears to have found its footing.