How many innings are in an MLB doubleheader? Breaking down baseball's twin bill

Doubleheaders are quite common in the game of baseball. The sport is played outside in the summer, when the weather can quickly take a turn for the worst, canceling games.

Recently more and more teams have opted to have a retractable roof in their stadiums. This decreases the chances a game gets called due to bad weather, but not every stadium has one.

There was some bad weather in the St. Louis area on Friday. This caused the game between the St. Louis Cardinals and Washington Nationals to be rescheduled. The two teams played a doubleheader on Saturday, with each game being nine innings, also known as a twin bill.

MLB doubleheaders used to be limited to seven-inning games when the Covid-19 pandemic was at its strongest. This rule was wiped away in 2022 as the league, and MLBPA signed a collective bargaining agreement. While it was a fun experiment, many in the league considered the seven-inning games to be little league.

MLB doubleheaders are becoming rarer with each passing season

Cleveland Guardians v Texas Rangers

More and more teams opt to take a page from the Milwaukee Brewers' playbook and have a retractable roof. The Texas Rangers have the newest stadium in the league, and one of its biggest selling points was its retractable roof. Given how hot it gets in Texas, this helps players and fans.

Eight teams now have a stadium with a roof over their heads. Seven are retractable roofs, while the Tampa Bay Rays play in a fixed dome at Tropicana Field.

As more stadiums get revamped, more retractable roofs will be added. This helps eliminate the possibility of any bad weather and allows teams to alter how their field plays. Closing the roof will allow for more offense, while keeping the roof open can limit the pop off the bat.