The National League West had the majors’ two winningest teams, and also the three best performances by a National League general manager in 2021.
It also had the only mid-season front office shakeup in MLB in 2021, that occurring in Colorado.
Our standard for evaluating the performance of a general manager (or other chief executive who holds a functionally similar title) is simple. We attach a value to every personnel move made by the since the conclusion of the 2020 season last October. The sum of the values is the GM’s rating.
The value is determined by the Wins Above Average (WAA) generated by the player during 2021. WAA is an offshoot of WAR, and it is ideal for this purpose because unlike WAR it is zero-based. That means if we say a GM impacted his team by +2.5 games in 2021, he cumulatively improved his team’s fortunes by that many games.
Conversely, a GM with a negative cumulative WAA can be said to have hurt his team’s pennant prospects by that amount.
General manager rankings evaluation, explained
Broadly speaking, a general manager can impact his team in any of five ways: by the trades, purchase and waiver claims he makes, by his free agent signings or extensions, by his farm system callups, by the players he trades away, and by the players he releases or loses to free agency.
Each general manager should, of course, be judged in the context of what they are attempting to accomplish. As an example, Cubs general manager Jed Hoyer conducted a mid-season tear-down of his roster that was virtually guaranteed to produce a negative rating for Hoyer by season’s end.
Hoyer would probably be OK with that; the moves were designed for future, not present impact.
In the end, the best way to understand the rating is this: It tells how much better or worse a GM made his team’s roster compared with what would have occurred had he (or in the case of the Miami Marlins, she) done nothing at all.
For that reason, the ratings do not necessarily correlate with the final standings. Some GMs are starting from a better position than others.
With that as an explanation, here’s how the six NL West general managers scored in 2021.