Mark Simon also contributed to this article.

One of the cool items in the SIS toolkit is our injury prediction model.

This is something we make available to teams and not the public, though we share an excerpt in The Bill James Handbook 2023 from which I’ll share a little bit here.

Our projections come from a comprehensive injury database. We log nearly everything deemed significant to a player’s physical health – not only whatever we can glean from media reports, but even something as inconsequential as a batter fouling a ball off his body or a pitcher being struck by a batted ball.

We take that injury data, factor in a player’s workload, position, body type, and playing style (does he slide, dive, jump a lot) to figure a likelihood of an injury worthy of an IL stint or missing 10 days of playing time. Seven of the top likeliest batters to sustain an IL-worthy injury in 2023 spent time on the IL in 2022.

If you want to learn more about what goes into the projections, watch our presentation from the 2021 SABR Analytics Conference.


If you don’t have time to watch the video, among the most important inputs for a hitter are his speed score (a stat combining six indicators, including frequency of steal attempts and double plays, triples, and fielding range), his Body Mass Index (BMI), age, and the number of days since his last injury.

With all this in mind, who are the free agent position players who rated most likely to need at least one IL stint in 2022?

Our No. 1 is shortstop Xander Bogaerts. Bogaerts actually ranked third in our injury projections entering 2022 but played in 150 games and avoided the IL. However, most of his games missed were acknowledged as being due to an injury rather than scheduled rest. He left four games early due to injury (hamstring, back) and was taken out of the starting lineup four other times due to lingering back or hamstring issues. These minor injuries do factor into our projections.

Also, since 2021 Bogaerts boasts the second-highest number of sliding, diving, and jumping plays, with 150. Bodily sacrifice impacts our injury projections. Given that Bogaerts has recorded an out on 10 of his last 72 dives, it may be better for him to taper that approach as he starts his new contract.

No. 2 on the list is third baseman Justin Turner. This isn’t that surprising given that Turner is old (he just turned 38) and has a history of injuries. He had one IL stint last season, missing 16 games in a 17-game stretch with an abdominal strain. It’s worth noting that Turner hit considerably better after returning from the rest, hitting .314 with an .878 OPS in his last 41 regular season games.

Turner is another who might be served by cutting back. He’s the oldest player with at least 50 slides, dives, and jumps in the last three seasons (he has 80).

The No. 3 highest-risk free agent in our projections is second baseman (and former shortstop) Jean Segura and that shouldn’t be that surprising. Segura missed 54 games last season when he broke his finger after getting hit by a pitch. He twice spent time on the IL in 2021, once with a strained groin and once with an injured quad.

Segura is 5-foot-10 and played at between 205 and 220 pounds the last few seasons. As noted earlier, BMI is one of the most important inputs in our projection tool, so his build joins his recent injury history and age as contributing factors in this projection.

The 2023 Bill James Handbook has the top 10 hitters and top 10 pitchers in our injury projections (Bogaerts and Turner were No. 1 and No. 2 among all players). You can purchase the book at ACTA Sports or wherever you buy your books.