Fastpitch rules guide

The softball DP/FLEX rule, the EP and re-entry, explained

Three rules decide who bats and who fields in fastpitch softball: the DP/FLEX, the extra player (EP) and re-entry. Here's how each one works under USA Softball's 2026 rules, in plain English, with the lineups they produce.

The lineups at a glance

JO is Junior Olympic, USA Softball's youth fastpitch play. The EP and batting the roster are JO rules; the DP/FLEX works in adult fastpitch too.

The DP/FLEX rule

The designated player (DP) bats for one player in the field. That player, the FLEX, plays defense but doesn't bat. Think of it as one batting spot shared by two people: the DP hits, the FLEX fields.

Coaches use it to get a strong bat into the lineup without giving up a glove, or to let a pitcher or catcher focus on defense.

Setting it up

• Declare it before the game. The DP takes a spot in the batting order, and the FLEX is listed last on the lineup card.
• The DP keeps that batting spot for the entire game.

What can change during the game

• The FLEX can bat, but only in the DP's spot. The DP then leaves the game and you're down to nine players. The starting DP can re-enter once, in the same spot, and the FLEX then goes back to defense only or leaves the game.
• The DP can play defense, at any position. If the DP fields for someone other than the FLEX, that player keeps batting and just stops fielding. Nobody has left the game.
• If the DP takes the FLEX's position, the FLEX has left the game and you're down to nine. The FLEX can re-enter once, either back in the last spot on the card or in the DP's batting spot.
• The FLEX can be replaced by a substitute, an EP or the DP.
• The one hard line: putting the FLEX into a batting spot for anyone other than the DP makes the FLEX an illegal player, and an illegal player is disqualified.

An example

Jordan is one of your best hitters but not your best catcher. Riley is your best catcher but is struggling at the plate. List Jordan as the DP, batting fifth, and Riley as the FLEX at catcher, last on the card. Jordan hits in the fifth spot, Riley catches, and neither one sits.

In the fifth inning you want Riley's bat. Riley hits in Jordan's spot and keeps catching, Jordan leaves the game, and you're playing nine. Jordan can still come back once, in the fifth spot.

The extra player (EP)

The EP is an optional extra batter. Adult fastpitch bats nine; the EP is a Junior Olympic (and slow pitch) rule.

• Declare the EP before the game and list the EP in the batting order. In JO the EP can bat anywhere in the order.
• The EP keeps the same batting spot and must be used for the whole game.
• Any 9 of your 10 batters can play defense. Report any change at pitcher or catcher to the plate umpire.
• The EP can be replaced at any time by a player who hasn't been in the game yet, and the starting EP can re-enter once.

DP/FLEX plus an EP

JO teams can use both: 11 players with 10 batting. The FLEX still fields without batting, and every DP/FLEX rule above still applies. The trap: if one of your 10 batters goes in to play defense for the FLEX, that's a substitution, and the FLEX has left the game. USA Softball's umpires have ruled on this exact play.

Pool play: bat the roster

In JO pool play a team can bat everyone present instead of nine. The extra batters are listed as EPs and can play any position. One catch: while you're batting more than nine, a player who leaves the game for any reason other than injury or ejection costs your team an out, and an injured player's spot is skipped with no out.

Re-entry: once, in the same spot

• Any player, starter or substitute, can be replaced and come back once, in the same batting spot.
• A starter and their substitute can't both be in the lineup at the same time.
• Coming back a second time, or in a different batting spot, is an illegal re-entry, and the player is disqualified.

Example: Casey starts and bats seventh. Sam pinch-hits for Casey in the third inning. Casey can come back in the fifth, still batting seventh, and Sam leaves the game. If Casey comes out again, Casey is done for the game. Sam has one re-entry too, in that same seventh spot.

Other rulebooks

This guide follows USA Softball's 2026 rules. High school (NFHS), college and other youth organizations have their own versions of the DP/FLEX, the extra hitter and re-entry, and plenty of leagues and tournaments write their own. They're close but not identical, so check what your league or tournament plays before the first pitch.

Running it from the dugout

Next Inning handles softball lineups on a phone or tablet:

• Set how many bat, 9, 10, 11, 12 or everyone, for the team or for one game.
• Mark the DP, FLEX and EP for each game. The dugout and the fielding plan tag them, so nobody has to remember who bats for whom.
• A pinch hitter takes the same batting spot, and nobody else moves.
• It flags a FLEX batting anywhere but the DP's spot. Turn on the Re-enter once setting and it also warns before a player comes back a second time or in a different spot. You can still make the move: the umpire, not the app, has the last word.
• The generated fielding plan keeps the DP and EP off the field and a declared FLEX on it, and DP and EP innings don't count against your fielding playing-time rules.

Prefer paper? The free printable lineup card has room for 12 batters plus a sub. For the fairness side of the lineup, see how to build a fair youth lineup.

Rules summarized from the 2026 USA Softball Official Rules of Softball, Rule 4, Sections 1, 3, 4 and 5. Next Inning is not affiliated with USA Softball.

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