Field sizes by division
- Minor Division: Bases are to be 60′ apart; Pitching distance is 45′
- Junior Division: Bases are to be 70′ apart; Pitching distance is 50′
- Senior Division: Bases are to be 90′ apart; Pitching distance is 60′ 6″
“Mercy Rule” & 5-Run Rule
JBO has a 10-run "Mercy Rule" for all divisions and levels during league play. The 10-run "Mercy Rule" provides that a game will end after 5 innings for Seniors, 4 innings for Juniors and Minors, or any inning thereafter, when a team is 10 or more runs behind and has completed its turn at bat.
The “5-Run” rule states that there will be a 5-run rule per inning with the final inning open. The umpire must declare, prior to the start of any inning, that this is the final inning, based on the following conditions: time restriction, field condition, darkness or the final inning.
| Skill Level / Division | 5-Run Rule |
| Senior Federal / Senior American | No |
| Senior National |
Yes |
| Junior Federal / Junior American | No |
| Junior National | Yes |
| All Minor Levels | Yes |
Game Length
| Minor | Junior | Senior | |
| Official End of Game |
After 5 innings 4 1/2 innings if home team is ahead |
After 6 innings 5 1/2 innings if home team is ahead |
After 7 innings 6 1/2 innings if home team is ahead |
| Due to Weather or Darkness | 3 innings constitute a legal game 2 1/2 innings if home team is ahead |
4 innings constitute a legal game 3 1/2 innings if home team is ahead |
5 innings constitute a legal game 4 1/2 innings if home team is ahead |
If a legal game is not completed, the game is a continuation.
- For Junior National and Minor National Divisions, no new inning will start after 2 hours playing time.
- For Senior National Division, no new inning will start after 2 1/2 hours playing time.
In the case of Weather or Darkness:
- If a legal game is completed, both teams have had an equal number of complete turns at bat and the score is tied, it is a continuation.
- If a legal game is completed, both teams have not had an equal number of complete turns at bat and the score is tied, the score shall be the same as it was at the end of the last completed inning. If the score was tied at the end of the last completed inning, then the game is a continuation.
To report a continuation, fill out the game report form and indicate that the game was suspended. Pitch counts for the game should be reported, along with the score and number of innings completed at time of suspension.
Fielding a Team: Teams are allowed 15 minutes to field a team of nine players prior to the declaration of a forfeit. For National level, a team can play with eight players. Each time the ninth spot comes up to bat, an out is given. If the line-up drops below eight, then the game will be a forfeit. Each team will bat its entire roster.
Each player must play a minimum of 6 defensive outs (9 for Senior level). If a player arrives late and is unable to complete his/her defensive outs, they must be inserted immediately and play until the game is completed or they have played their required 6 defensive outs. A player arriving after the game has started will be inserted at the end of the batting lineup.
Injuries: If a player misses their at-bat due to any reason, or is injured while on offense and has to be removed from the field of play, he/she will be removed from the lineup and the game will continue. The player cannot return to the lineup for the remainder of the game. All other players will continue to bat in the same order. If, by removing the injured player from the lineup, the team drops to 8 players, then the player who was removed will count as an “out” each time it is his turn at-bat. If, by removing the injured player from the lineup, the team drops to 7 or fewer players, the game is a forfeit.
