The all-time saves leader twisted his knee while shagging flies in the outfield before tonight’s game in Kansas City. A fan who watched the video reports, “Rivera’s knee buckled and he landed awkwardly, and he was in severe pain.” Not good news if you’re a Yankee fan, though perhaps baseball’s best set-up man will become its best step-up man too.

UPDATE: Torn ACL. Probably a career ender.