The Opening Ceremony is scheduled for 6.30 pm in Ciudad Obregon on Thursday, 23 September.
The teams will start the tournament with a group stage (round-robin):
- Group A Ciudad Obregon: Mexico, Czech Republic, Dominican Republic, Cuba, Germany and Chinese Taipei
- Group B Hermosillo: Colombia, Korea, Netherlands, Nicaragua, Panama and Venezuela
Germany and Chinese Taipei will open Group A at 10:30 a.m. local time in Ciudad Obregon, while the Panama-Colombia 10:30 a.m. game will serve as the Hermosillo Group B opener.
The hosts and defending U-23 World Champions, Mexico, will take the field at 7.30 pm against the Czech Republic in Ciudad Obregon.
The top three finishers from each group will advance to the Super Round, which will be played from 29 September to 1 October. The finals are set for Saturday, 2 October.
The WBSC previously ruled to expand the age category for the upcoming edition of the WBSC U-23 Baseball World Cup in Mexico to include players up to the age of 24 due to the one-year postponement of the event to the COVID-19 pandemic. Accordingly, players born in 1997, 1998, 1999, 2000, 2001, 2002 and 2003 will be eligible to participate in the 2021 WBSC U-23 Baseball World Cup.
The II WBSC U-23 Baseball World Cup was played in 2018 in Barranquilla, Colombia. Mexico defeated Japan, 2-1 in the World Championship Final, while Venezuela bested Korea, 5-4, to earn the bronze.