Can the Chicago Cubs fix what’s wrong with Alec Mills?

Alec Mills is no superstar, but he will nevertheless matter to the Chicago Cubs next year. However you slice it, the starting rotation at the moment has more holes than Swiss cheese. Aging Jedi Kyle Hendricks will be there, newcomer Wade Miley will join him and Hendricks’ young apprentice Adbert Alzolay is probably a safe bet, as well. After that, it’s anyone’s guess. Reports that the team has reached out to Milt Pappas remained unconfirmed at press time.

Mills can plug one of the rotation holes, but only if he develops further. At a 88.7 MPH average velocity, his four-seam fastball would have been the second-slowest fastball in all the land had he pitched enough innings to qualify. Only Hendricks’ was slower.

The good news is that Mills has four other and better pitches. Based on Fangraphs’ pitch-specific information, Mills’ other pitches (sinker, changeup, slider, curve) have all been a bit above average through his career. Statcast paints a similar picture; using almost any metric, his other pitches outperform the four-seamer. In terms of run value, the four-seamer has always been one of his two least effective pitches. His other pitches feature good to excellent movement.

This suggests one obvious adjustment Mills could make: throw fewer four-seamers. And that’s exactly what he’s been doing,  His four-seamer usage has dropped every season since 2018, falling to just over 17 percent this year. He’s turned most of those missing four-seamers into sinkers, easily his most frequent offering in 2021, and a pitch on which he gets a tick more velo.

His eye-watering 5.07 ERA last season suggests these adjustments have not helped, but other run suppression measures tell a more positive story (4.79 xERA, 4.49 FIP. 4.33 xFIP). His BABIP against was .323 in 2021, a career worst. He’s generating softer contact (albeit still with more hard hit balls than average), absolutely critical for a man who will never miss many bats.

Chicago Cubs need Alec Mills to level out his righty-lefty splits in 2022

So Mills is already on his way to become a serviceable rotation option. The biggest hole in his game, as reported recently on this very site, is that lefties pulverize him. Mills had a standard approach last season: mainly fastballs (both kinds) and sliders to righties, mainly sinkers and changeups to lefties. While he didn’t throw many sliders to lefties, those that he did were more effective than the sinker. Indeed, against both sides he might benefit from mixing in a few more of the “other” off-speed pitch (more changeups to righties and more sliders to lefties), maybe using these to replace a few more of his remaining four seamers.

There may be reasons, sequencing for example, why this won’t work, but it wouldn’t hurt if pitching coach Tommy Hottovy and his promising new assistant help Mills explore any sensible options along these lines.

Mills is an average defender on the mound; as a reliable groundball pitcher, he might benefit as much as anyone from some extra PFP. Of course, bringing back Javy would be better.

By the time you read this, Mills will probably have turned 30. He’s unlikely to play a key role on the Cubs next postseason team, barring expanded playoffs and Hoyer’s kidnapping of the entire Rays player development operation. But every team needs to get value out of players like this on the off-chance the playoff train arrives early, and otherwise to provide trade possibilities and help younger players learn the ropes. Mills may not be the next Scott Feldman, but he doesn’t have to fetch that kind of return to be useful.