Morning Mound Visit: sabermetrics news - 9/21/19

FanGraphs | Dan Szymborski: Nicholas Castellanos has been a great story of the second half, hitting to a .330/.365/.665 after being traded to the Cubs. Yet teams’ opinions of him probably don’t change dramatically in a few months, which isn’t great news for a player who probably won’t get his due in free agency.

The Ringer | Ben Lindbergh: Luis Severino made his Yankees debut, and he could really help the team in the postseason. There is some precedent for late-season additions via IL returns yielding big results; David Price increase World Series odds by 14% in 2008, or Julio Urias increased them by 8.77% last year. Those are really the tops, but you can see how one single player, in one or two big spots, can swing the season in one direction.

ESPN Insider | Bradford Doolittle ($): There are just a few games left down the stretch, and it could be craziness with the Cubs, Cardinals, and others vying for a spot, and here are some of the crazier outcomes we’ve seen in history.