In the interest of player health and safety, Major League Baseball and the MLB Players Association jointly announced Friday that both games of doubleheaders will be seven innings in length for the duration of the 2020 season. The change will be effective Aug. 1.

In these doubleheader games, the automatic runner, which is part of the new extra-innings rule in place for the 2020 regular season, will be placed on second base to start each half-inning after the seventh, rather than after the ninth. 

The rules determining when games become official -- 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 -- will remain the same.

Doubleheaders featuring two seven-inning games are common in both college baseball and Minor League Baseball.

However, according to the Elias Sports Bureau, the only MLB doubleheader in the Modern Era (since 1900) to feature two games of seven innings or less came on Sept. 19, 1912, between the Indians and Red Sox at League Park in Cleveland. The first game was five innings and the second game was six innings. The last doubleheader that was a total of 14 or fewer innings was on May 29, 1915, between the Pirates and Cardinals at Forbes Field. The first game was five innings and the second game was nine innings.

The specific rule has been amended as follows:

Notwithstanding anything to the contrary in Official Baseball Rule 7.01(a) (“Regulation Games”), a regulation game in both games of a double-header shall consist of seven innings, unless extended because of a tie score. In this respect, the "Extra Innings" rule contained in Section 5.1.2 of the 2020 Operations Manual shall apply to each half-inning following the completion of the seventh inning.

Please note that OBR 7.01(c) shall still apply, such that if a game is called, it is a regulation game (1) if five innings have been completed; (2) if the home team has scored more runs in four or four and a fraction half-innings than the visiting team has scored in five completed half-innings; or (3) if the home team scores one or more runs in its half of the fifth inning to tie the score.