MLB: Ranking the decade’s best general managers

The 10 most successful general managers in MLB of the decade. The ranking is based on the cumulative WAR of players brought into the organization by the GM.

In these hyper-analytical days, the fates of teams rise and fall with the decisions made by their front offices. That makes the success of a team’s front office chief – commonly although not always the general manager – vital to on-field performance.

As the second decade of the 21st Century concludes, it’s a good time to assess the performances of the decade’s best front office bosses.

Our standard of measurement is the total Wins Above Replacement (WAR) generated by the players acquired by each GM during the decade.

That value is calculated both on a short-term and long-term basis. Simply put, short-term value is the value contributed to the team by players obtained since the conclusion of the preceding season. Long-term value is the value contributed to the team by players who had been obtained prior to the conclusion of the preceding season.

Generally speaking, players can be acquired in any of several ways: by trade, purchase or waiver claim, by free agency, or by farm system development.  For our purposes, however, the method of acquisition is irrelevant.

All general managers who ran an MLB  team for at least one season during the decade were considered, although – since the standard is cumulative WAR – tenure plays a role in the ranking.

None of the GMs who made the top 10 ran front offices for fewer than five seasons during the decade; three were in place for all 10…two of them with the same team.

Here are the top 10. Summary data includes the total number of games – as measured by WAR – they brought to their teams, and their tenures with each team they ran during the decade.