Chris Sale’s return, from a rehab professional’s POV

The narrative exists that Chris Sale is Boston’s "reinforcement" for the home stretch of baseball’s 2021 regular season, akin to a trade deadline acquisition. While that narrative fills sports journalists’ word count (and webpage clicks) quota very nicely, it’s only partly based in reality. Chris Sale is returning from ulnar collateral ligament reconstruction surgery (TJS, for short). This surgery has become much more common over the past decade — both the actual surgical procedure and post-operative rehabilitation have been refined and improved during that timespan.

Despite that increased commonality of TJS and the unconfirmed belief that pitchers’ elbows can be "better than before" the injury, this is still a major surgical procedure that carries a lot of risk. Those risks are too numerous to discuss in this context, but I at least need to mention the risk of re-injury. Just ask Nate Eovaldi (among others), who later needed a second TJS.

That’s not to say that Sale chose to have surgery carelessly or hastily. Trying to pitch without an intact ulnar collateral ligament is like a smaller version of crashing a car on its front end while not wearing a seat belt: some violent forces are going to go unopposed by any tensile restraint, and as a result, body tissue is gonna get injured. If you’re a MLB pitcher with a torn UCL in your pitching side elbow, you either accept the risks of TJS, or retire.

I’m sharing all this because I know there will be a lot of (perfectly valid) hype and excitement when Sale reclaims a MLB pitching mound on Saturday. It would be easy enough to argue that Sale immediately becomes the Sox’ best player once he’s finally off the Injured List. I think Sale will be great. However, it’s probably important for fans to temper expectations for Sale. He will still be in (the final stages of) his rehabilitation plan, for at least the next few weeks. "Medically cleared to participate" does not mean "100% rehabilitated". Won’t go too deeply into the physiology, but in brief, there is still important remodeling and conditioning of the ligament tissue happening. So, don’t expect 110-pitch performances from Sale anytime soon.

So, after that discussion, what do I expect from Sale? He will likely pitch approximately 50 innings (in MLB) in 2021, barring any setbacks, which are possible. He will throw 95 mph fastballs, but he’ll also throw some with less velocity, on purpose, and the 91-92 mph offerings should not cause panic among fans. We can also expect a few heaters that surpass 95 mph, but I’m sure Sale has been told to limit, or even avoid, maximum effort throws at this time. The goal is to increase workload (and tissue stress, which is not entirely measured by number of innings or pitches) gradually and incrementally over time. During Sale’s roughly 50 IP, I’d anticipate about 50 K’s, 10 walks, and 5 HR allowed.

Regardless of the statistical outcomes, what’s most important is that Sale builds endurance and confidence while remaining healthy, ready to open the 2022 season. That, and of course, the fact that we can once again celebrate #SaleDay.