As part of MLB’s health and safety protocols for the shortened 2020 season, the rain delay rules are a bit different than they've been in the past, but only for non-official games.
If weather causes a game to be cut short before it is official, it will be continued at a later date from the point of the stoppage. In previous years, games that were cut short due to weather before becoming official were restarted from scratch. At this point, these new rain delay rules are only in place for the 2020 season. In future years, MLB will likely return to the previous rules for non-official games.
Meanwhile, rules for a regulation game -- also known as an “official game” -- remain the same as they've been in previous seasons.
A game is considered a regulation game once the visiting team has made 15 outs (five innings) and the home team is leading, or once the home team has made 15 outs regardless of score.
If a game is tied after becoming official, it will be completed at a later date.
But if weather causes a game to be cut short after it is official and the game isn’t tied, the results will stand, as we saw in the Yankees’ 2020 Opening Day win over the Nationals in Washington. New York was leading, 4-1, in the top of the sixth inning at the time of the rain delay. The game was eventually called, giving the Yankees a 4-1 victory.