Cubs Notes 7/8/23

The upcoming trade deadline has me thinking about the Cubs’ two most prominent potential trade pieces, Cody Bellinger and Marcus Stroman.

Cody Bellinger Has Been a Win and a Miss

With the Cubs struggling, I’ve thought a lot about which moves they missed and didn’t miss over the offseason. Trey Mancini, Eric Hosmer, Edwin Rios, Brad Boxberger, and Jameson Taillon have been bad, but Dansby Swanson, Cody Bellinger, and Mike Tauchman have been good. In many cases, the alternatives haven’t been much better (see José Abreu, Christian Vázquez, Jacob deGrom). One choice I had forgotten about, however, was that between Bellinger and Kevin Kiermaier.^[1]

Kiermaier has been healthier than Bellinger this year, which is unusual; Bellinger has played in 38 more games over the last three years. Both are good defensive center fielders, though Kiermaier is a generational talent there. The number that stands out to me, though, is their xWOBAs. The way Kiermaier has hit thus far would typically result in better outcomes than those Bellinger has gotten. Bellinger’s expected production has matched Nick Madrigal, Mike Tauchmann, and Nico Hoerner’s actual production. This doesn’t mean that Kiermaier will be the better hitter going forward (xWOBA is a descriptive stat, not predictive), but he has actually been the better hitter over the last three years and worth nearly three more wins. Kiermaier lacks the MVP ceiling that Bellinger has, but his floor is higher despite availability concerns, and he’s making $8.5M less this year.

This isn’t to say that Bellinger has been a bad signing. The Cubs are a better team when he’s playing, and they certainly don’t regret the one-year commitment they made to the center fielder. When the topic of a Belinger extension comes up, though, I can’t help but think about Kiermaier. I would love if Bellinger signed up for another year with the Cubs, but that doesn’t mean he’s their best or only option. Depending on his contract demands, it might not be worth paying for his MVP upside anymore.

Checking in on the Rotation

The Cubs pitching staff is difficult to analyze since they all rely on getting weak contact. In the table above, I included three ERA estimators: FIP takes into account home runs allowed, strikeouts, and walks; xFIP is FIP but with a league average home run rate; xERA takes into account quality of contact given up by a pitcher. There is no one true pitching stat, and they all offer different views of pitchers. For example, by ERA, Kyle Hendricks has been one of the best pitchers in the National League. He doesn’t strike a lot of guys out, but he also doesn’t walk many batters and has given up just two home runs, so FIP says he’s gotten some help from his defense, but is still a good pitcher. xFIP assumes that Hendricks doesn’t have a special ability to prevent fly balls from becoming home runs, sees the second-highest fly ball rate of his career, and predicts that he’ll be a below league average starter if he continues pitching the same way. xERA paints a rosier picture since it takes into account Hendricks’ ability to generate weak contact and says he’s been a roughly league average pitcher. In this case, I’m inclined to agree with xERA the most.

This comparison is also relevant when discussing Marcus Stroman. Despite a recent rough stretch, Stroman has an excellent ERA. Looking at the underlying stats, Stroman has still been a great pitcher, but not dominant. Before Smyly’s latest start, he and Stroman had the same xERA. I would certainly bet Stroman is the better pitcher going forward, but it’s no secret that his style of pitching relies on good defense and some luck.

Stroman tweeted about asking for an extension when he was in the middle of one of the best stretches of his career. He has a player option for $21M next year, which he seems almost certain to decline unless he suffers a season-ending injury. I have no idea what kind of contract Stroman is seeking or what will be available to him this offseason, but if he wants to maintain his current salary I could see something like $100M over four years, which would pay him like an ace (at least in terms of annual value). Stroman is a good starter, but I'd rather have Hendricks for his $16M club option next year than Stroman for four or more years at a high average annual value.

I’m not against holding on to or extending either Stroman or Bellinger. If they both want to be paid like their surface numbers suggest, though, it could be hard to find a middle ground. At some point, the Cubs need to keep good players, but every situation is different. The team will need to take into consideration the optics of trading away good players for the third consecutive year, the available alternatives to those players, and the benefits of keeping two of the best players available at the trade deadline.