Currently, the World Baseball Classic's main tournament includes 20 nations, an expansion from the 16-team fields of the first four WBCs held between 2006 and 2017.
For the fifth edition of the WBC, to be held in 2023, the 16 participating nations from 2017 all received automatic berths; the remaining four slots were filled by the winners and runners-up of two six-team qualifying tournaments.
[2] With the fifth edition of the WBC's main tournament expanding from 16 teams to 20, there was no relegation as all 16 participating nations from 2017 were given automatic berths.
The qualifying round was reorganized into two six-team tournaments, with the winners and runners-up advancing to the main event.
Qualifying for the fifth WBC was originally scheduled for March 2020, with both tournaments planned to take place in Tucson, Arizona.