The designated player and FLEX
WBSC · 2026–2029The optional DP/FLEX arrangement must be declared in the starting line-up. It uses 10 listed players but only 9 batting positions. The designated player bats, while the FLEX is listed in the non-batting position and plays defense. This is not an extra hitter added to the batting order.
The rule
The optional DP/FLEX arrangement must be declared in the starting line-up. It uses 10 listed players but only 9 batting positions. The designated player bats, while the FLEX is listed in the non-batting position and plays defense. This is not an extra hitter added to the batting order.
In practice
The DP may play defense for another player, who can remain in the batting order. If the DP plays for the FLEX, the line-up shrinks; the FLEX may enter on offense only in the DP’s position. They cannot both participate on offense at the same time. Such changes must respect reporting, substitution and re-entry requirements.
Sources & approach ↗