Southpaw Roulette: Assessing the Cubs Left-handed Bullpen Options

At this point in the off-season, the Cubs have a pretty good idea what their roster might look like on Opening Day. While they might tinker on the fringes and try to get a bargain in January/February, I thought this would be a good time to evaluate the internal options for left-handed relief in the bullpen. We have seen some turnover in this department from last year. World Series hero Mike Montgomery is slated to make the move to the starting rotation while jack-of-all-trades Travis Wood is expected to move on to another organization—barring a late off-season push by the Cubs. While the Cubs have a plethora of options to get left-handed hitters out, there isn’t a ton of experience or track record among much of the group.

Brian Duensing
The elder-statesman of the group, Duensing has by far the most experience of the core group of left-handed options. A former starter for the Twins, he will be entering his ninth season in the big leagues. He was limited to just 13 and 1/3 innings last year in the majors with the Orioles. Duensing actually has a deep repertoire for a reliever, but he’s primarily fastball/sinker and slider against left-handed hitters. He also mixes in a change-up and a curveball, but he doesn’t throw them as often versus lefties. He definitely fits the LOOGY role rather than a full inning type of guy. For his career as a reliever, he has given up .755 OPS to right-handed hitters but only a .622 OPS against left-handed hitters. The strikeout and walk numbers are also quite a bit better against lefties than against righties. Against righties as a reliever, Duensing has a career K-BB% of just 1.7%. That number jumps all the way up to 14.1% against lefties. As a veteran on a big league contract, Duensing probably has the inside track to be one of the lefties in the pen.

Caleb Smith
A rule 5 pick in December from the New York Yankees, Smith is probably the favorite to fill the role of the second left-handed reliever in the bullpen for a couple of reasons. The first is that because he’s a rule 5 pick, the Cubs have to keep him on the roster the whole year or they have to return him to the Yankees organization. The second reason is that Smith is a long reliever/swingman, which is something the Cubs don’t currently have in the bullpen. In 2016 in AA Trenton in the Yankees organization, Smith struck out an impressive 25.1% of batters he faced in 27 appearances (7 starts). While the ERA might not look great at 3.96, his unusually high .344 BABIP against and 66.7% LOB% likely have something to do with that. While it might be rushing him to the big leagues, the Cubs really like the stuff and Smith will likely have a chance to carve out a role early given the nature of how he was acquired.

Jack Leathersich
Leathersich is now in his second year in the Cubs organization after being acquired by the Cubs on waivers in 2015. He returned from Tommy John surgery last year and reached AAA late in the year. Leathersich is an interesting guy because of how dominant he has historically been in his minor league career. He has struck out a remarkable 390 batters in just 234 career innings pitched since being a professional. While he doesn’t light up the radar gun, Leathersich sits in the low 90s with a really good slider. While the chances are good he starts the year at Iowa, look for Leathersich to get an opportunity at some point in 2017 with the big league team. If he can keep the walks under control (about 5 per nine in his minor league career), chances are he could be a very effective reliever in the majors.

David Rollins
Rollins has had quite the off-season so far. Originally claimed by the Cubs on November 18th from the Mariners, he was then claimed by the Rangers, the Phillies, the Rangers again and then the Cubs again, all in the span of just over a month. If he can go the rest of the off-season without being claimed, Rollins gives the Cubs another option with a bit of big league experience. He had some decent numbers peripherally (17.8% K vs. 6.8% BB) in 25 innings in 2015 with Mariners, but he still posted a 7.56 ERA. In just 9 1/3 innings in 2016 with Seattle, the walks ticked way up and the strikeouts were down. While Rollins is likely a long-shot to make the roster out of Spring Training, he provides the Cubs with some depth in Iowa from the left-side.

Zac Rosscup/Gerardo Concepcion
Both Rosscup and Concepcion have time in the majors with the Cubs in the recent years. Both of them were removed from the 40 man earlier in the off-season, but both decided to rejoin the Cubs organization on minor league deals. Neither has a great chance of making the big league team out of Spring Training, but keep an eye on both of them throughout the year. Rosscup is especially interesting as a guy who has always had the stuff to get hitters out, but has had trouble with both walks and staying healthy.

Koji Uehara
But Tommy, why is Uehara on this list, isn’t he right-handed?? Why yes…yes he is. The reason I included him on here is because his splitter gives him a weapon that helps him neutralize left-handed hitters. Throughout his career, Koji has done a great job of keeping lefties at bay. Over his eight MLB seasons, lefties have just a .181/.220/.335 line against him. Because of this, the Cubs might be able to get away with carrying only one left-handed reliever in the bullpen. The idea of reverse split guys is something we’ve seen the Cubs utilize in the past, primarily with Justin Grimm, whose curveball gives him a great weapon against left-handed hitters. While Uehara might have needed to fill a late-inning role with other teams, the Cubs have the luxury of using him differently thanks to the presence of guys like Wade Davis, Pedro Strop, Hector Rondon and Carl Edwards Jr. The Cubs still very well might carry two lefties in the pen, but because of Uehara don’t be surprised if they decide to only roll with one.

Mike Montgomery
The last potential option for a lefty in the bullpen is Mike Montgomery. Yes, I did say earlier in the article that he is currently penciled in as the fifth starter, but it’s no surprise that the Cubs are constantly shopping around for starting pitching. A trade or perhaps a free agent signing of a guy like Tyson Ross (who could be deciding as soon as this week) could very easily push Montgomery back to the bullpen, where as we all know he had a great deal of success last year. This is probably my preferred option for how things go. While he could be an important starter moving forward post-2017, the Cubs are probably better off with him in the bullpen this year. The addition of a high-end lefty like Montgomery in the pen would definitely give the Cubs one of the deepest and best bullpens in baseball.

While these are most of the Cubs internal options for the bullpen from the left side, I also wouldn’t rule them out for adding another arm or two, depending on who is still available in the coming months. Multiple intriguing options are still on the free agent market including fan favorite Travis Wood, Jerry Blevins, and Boone Logan. That is a market the Cubs are surely monitoring given their lack of experienced options from the left side.

Lead photo courtesy Tommy Gilligan—USA Today Sports

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5 comments on “Southpaw Roulette: Assessing the Cubs Left-handed Bullpen Options”


Good rundown. I’ll be curious to see how Rob Z fits in this mix as well.

Tommy Meyers

Much appreciated! I would have thought that Rob Z would have been a good candidate, but it looks like the Cubs want to use him as starting depth down in Iowa so we’ll see. At the very least, he could be useful down the stretch.


That seems like a sound strategy. He’s one of the few upper minors arms with starter potential.

The CHI Sports Fan (@TheCHISportsFan)

Incredibly informative…

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