High Quality Content by WIKIPEDIA articles! The 1981 National League Division Series (NLDS), the opening round of the 1981 National League playoffs, began on Tuesday, October 6, and ended on Sunday, October 11. The Division Series were created on August 6 in response to the 1981 Major League Baseball strike, which caused the cancellation of roughly one-third of the regular season between June 12 and August 9; by the time play was resumed, it was decided that the best approach was to have the first-half leaders automatically qualify for postseason play, and allow all the teams to begin the second half with a clean slate.