Pursuant to Official Baseball Rule 5.09(b)(3), "any runner is out when they intentionally interfere with a thrown ball; or hinder a fielder attempting to make a play on a batted ball."
Replays indicate Báez jumped after Williams began his throw toward first base in an attempt to double up Báez for failing to tag up on the air out, which is indeed interference, as long as the umpire deems the runner's actions were an intentional attempt to hinder or impede the defense from making a play (in this case, completing the throw to first base). Replays indicate 2B Umpire Diaz did not signal interference, which by rule, suggests he did not deem Báez's act as intentional in accordance with OBR 5.09(b)(3).
The definition of offensive interference is "an act by the team at bat which interferes with, obstructs, impedes, hinders or confuses any fielder attempting to make a play."
Video as follows:
Alternate Link: Baez jumps into thrown ball, but interference isn't called...should it have been?
Video as follows:
Alternate Link: Baez jumps into thrown ball, but interference isn't called...should it have been?
