Major League Baseball and the players' association have agreed to a number of rules for the 2021 season.

The two sides agreed to health protocols, seven-inning doubleheaders and runners on second base to start extra innings for the second-straight season. The deal did not include last year's experimental rule to extend the designated hitter to the National League or expanded playoffs.

There were 78 extra-inning games last year, the longest of which went 13 innings (twice).

There were 45 games postponed for COVID-19-related reasons and just two were not made up in 2020.