Some things we all have in common are our nightmares. Being trapped, falling or being chased are themes that are likely familiar to any person having a bad dream. While nobody has ever done a study of the nightmares of general managers, they probably have a few extra templates: Their ace starter having a consultation with Dr. James Andrews; their cleanup hitter being suspended for using performance-enhancing drugs; their top prospect having something go pop in his knee. Unlike our dreams of being naked in English class or getting in an argument with Frank Tanana -- you guys get that one too, I hope -- these nightmares do come true.
While every GM probably tosses and turns in the night because of what's going on with the roster, the worries of Los Angeles Dodgers manager Don Mattingly and Texas Rangers manager Ron Washington have been worse than most this week. Clayton Kershaw, the 2011 and 2013 NL Cy Young winner will be out with back problems for at least two or three weeks. Yu Darvish, the ace of an injury-filled Rangers rotation, missed his Opening Day start because of neck pain. Each is expected to be back in short order, good news for the playoff hopes of both franchises. But teams aren't always so lucky, and these kinds of disasters do happen with regularity. If you don't believe me, just ask the Atlanta Braves.
But which players are the most difficult to replace? Whose loss would most affect a team's playoff chances? That's not a question that one can simply answer with wins above replacement, because that's a general evaluation of player ability and not quite as useful for these nitty-gritty roster details. Some teams are simply better equipped to handle certain losses than other teams. For a team like the Minnesota Twins or Chicago White Sox or Houston Astros, losing a star would hurt, but it wouldn't realistically affect the team's playoff chances.
To answer the question, I used the 2014 ZiPS projections, the playoff odds simulator and the likely Plan B's that each team would turn to in the event of the loss of each player in question. Below, I've ranked the 10 players whose loss for the season would most affect their team's playoff odds, ranked by decline in percentage points of a trip to October.