The 2021 Replacement-Level Killers: Introduction & First Base
In a race for a playoff spot, every edge matters. Yet all too often, for reasons that extend beyond a player’s statistics, managers and general managers fail to make the moves that could improve their teams, allowing subpar production to fester at the risk of smothering a club’s postseason hopes. In Baseball Prospectus’ 2007 book It Ain’t Over ‘Til It’s Over, I compiled a historical All-Star squad of ignominy, identifying players at each position whose performances had dragged their teams down in tight races: the Replacement Level Killers. I’ve revisited the concept numerous times at multiple outlets and have presented it at FanGraphs in an expanded format since 2018.
When it comes to defining replacement level play, we needn’t be slaves to exactitude. Any team that’s gotten less than 0.6 WAR from a position to this point — prorating to 1.0 over a full season — might be considered fair game. Sometimes, acceptable or even above-average defense (which may depend upon which metric one uses) coupled with total ineptitude on offense is enough to flag a team. Sometimes a team may be well ahead of replacement level but has lost a key contributor due to injury; sometimes the reverse is true, but the team hasn’t yet climbed above that first-cut threshold. As with Supreme Court Justice Potter Stewart’s definition of hardcore pornography, I know replacement level when I see it.
For this series, I’ll go around the diamond, pointing out the most egregious examples of potential Killers at each position among contenders, which I’ll define as teams who are above .500 or have playoff odds of at least 10.0%. That definition covers 17 teams (sorry Braves, Cubs, Cardinals, and Nationals, but you’ll have to do this without my help). If one of the aforementioned fringe teams gets their record or odds above the threshold this week, I’ll do an additional Very Special installment at the end. And while I may mention potential trade targets, I’m less focused on these teams’ solutions than I am the problems, because hey, human nature.
This first installment will cover first basemen. All statistics within this piece are through Saturday, July 17. Read the rest of this entry »

Jay Jaffe