2021 美国大联盟规则，已将6.01(a)(1)增订：
If a pitch that is not caught remains in the vicinity of home plate and it is
inadvertently deflected by the batter or umpire, that ball is a dead ball and
the runners should return to the bases they occupied at the time of the pitch
(but if the pitch was strike three, the batter is out).
捕手没有接到的球，在本垒区附近，反弹到打者或主审，
在不经意的情况下，造成球的偏转滚远，裁判应立即宣告比赛停止球，
垒上跑垒员必须返回投手投球前所占之垒。(若符合不死三振时，打者直接出局。)
以前原本是: 非故意的话比赛进行中，故意的话才是防碍守备。
范例详见苏建文的po文:
https://bit.ly/3ICmxNB