PO in Baseball — What It Means and How It Works

What Is a Putout in Baseball?

A putout is awarded to the fielder who is directly responsible for recording an out. The official scorer assigns the PO to whoever physically completed the play — catching the ball, applying the tag, or being at the base when a force out occurs.

It sounds simple, but the rules around who gets credit can get nuanced. The key rule: the putout goes to the fielder who last touched the ball to retire the runner or batter, or who tags the base on a force play.

Every Way a Putout Can Be Recorded

• Caught fly ball — Any fielder who catches a batted ball in the air records a putout. The most common type for outfielders.
• Force out at a base — The fielder covering the base receives the throw and steps on the bag before the runner arrives. The first baseman leads all MLB players in putouts almost every season because of this.
• Tag play — The fielder applies the tag directly to the runner. The tagger gets the PO, not the player who threw the ball (that player gets an assist).
• Third strike caught by catcher — Every time a pitcher strikes out a batter and the catcher catches the pitch, the catcher is credited with a putout. This is why catchers typically lead all fielders in POs over a full season.
• Strikeout — dropped third strike, throw to first — If the catcher drops the third strike and throws to first to retire the batter, the first baseman gets the putout, the catcher gets an assist.
• Batter called out on interference — The catcher receives the putout when a batter is called out for interference.
• Infield fly rule — The putout goes to the fielder who could have caught the ball even if they don't catch it.
• Batter hit by batted ball — The nearest fielder receives the putout when a batter is called out for being hit by their own batted ball.

Who Gets the Most Putouts — and Why

Catchers almost always lead all fielders in putouts over a full season, and the reason is straightforward: every strikeout where the catcher catches the pitch is a putout credited to the catcher. With MLB teams averaging 8–9 strikeouts per game per side, a catcher behind the plate for a full season accumulates putouts at a rate no other position can match through regular game action.

First basemen are a close second. Almost every groundout to an infielder results in a throw to first, making the first baseman the recipient of the putout even though the shortstop or second baseman did the harder work of fielding the ball. That's the difference between a putout and an assist — the infielder who fielded the grounder gets an assist, the first baseman who caught the throw gets the putout.

PO vs Assist — What's the Difference?

On a standard 6-3 groundout (shortstop to first base), the shortstop gets an assist and the first baseman gets the putout. On a 3U (unassisted first base), the first baseman fields the ball herself and records the out without a throw — that's an unassisted putout, and she gets no assist because no throw was involved.

PO in Baseball Scoring Notation

You'll also see PO appear in scoring notation when scorekeepers describe plays using fielder numbers. Each position is assigned a number: pitcher (1), catcher (2), first base (3), second base (4), third base (5), shortstop (6), left field (7), center field (8), right field (9).

A "6-3 putout" means the shortstop (6) fielded the ball and threw to first (3) for the out. A "4-6-3 double play" means second base (4) to shortstop (6) to first base (3). In each case, the last number in the sequence is the player who recorded the final putout.

PO as "Pitcher Only" — The Second Meaning

Outside of the box score, PO is also used to designate a pitcher-only player — someone who is on the roster exclusively to pitch and does not play any other position or bat in the lineup (in non-DH leagues).

You'll hear this most often at the high school and travel ball level. A coach might say "he's a PO" to mean that player isn't being developed as a two-way player — he specializes in pitching only. At the college level, most pitchers are POs. In MLB, all pitchers are effectively POs in the American League and most National League games since the universal DH was adopted in 2022.

If you see "PO" next to a player's name on a travel ball roster or tournament seeding sheet, it almost always means Pitcher Only, not putout. Context is everything.

PO in Softball — Same Stat, Same Rules

PO means exactly the same thing in softball as it does in baseball — a putout credited to the fielder who records the out. The same rules apply: catch a fly ball, record a force out, apply a tag, or catch a third strike, and you get a putout.

Catchers dominate putout totals in softball for the same reason as baseball — strikeouts are common and every caught third strike is a catcher putout. The main difference is that softball has a higher strikeout rate in some formats (particularly fastpitch), which can push catcher PO totals even higher relative to other positions.

PO in Baseball Betting and PrizePicks

If you're seeing PO in a DFS or betting context — specifically on PrizePicks or similar platforms — it typically still refers to putouts as a pitcher stat projection. Pitchers rack up putouts through caught third strikes (when their catcher records them, but strikeout totals are sometimes tracked differently across platforms) and fly outs where the ball is caught off their pitching.

On PrizePicks specifically, "pitcher POs" usually refers to outs recorded by the pitcher's defense, or in some cases is used loosely to describe strikeout-related defensive stats. Always check the platform's specific stat definition, as different DFS sites use PO slightly differently in their prop categories.

MLB Putout Leaders — Career & Single Season

First basemen dominate the career putout record books for the same reason they lead in single-season totals — every groundout to an infielder ends with a throw to first. Over a 15–20 year career, that adds up to tens of thousands of putouts.

Career Putout Leaders (MLB All-Time)

Single-Season Putout Leaders (MLB All-Time)

MLB Assist Leaders — Career & Single Season

Shortstops dominate the assist leaderboards for the opposite reason first basemen dominate putouts — they field the most ground balls and make the most throws of any position on the diamond.

Career Assist Leaders (MLB All-Time)

Single-Season Assist Leaders (MLB All-Time)

Understanding Putout Notation — 5-3, 9-3, and More

In baseball scoring, each defensive position is assigned a number. When you see a putout described as "6-3" or "5-3," those numbers tell you exactly which fielders were involved in the play.

What is a 5-3 Putout in Baseball?

A 5-3 putout means the third baseman (5) fielded the ball and threw to the first baseman (3) for the out. The third baseman gets an assist, the first baseman gets the putout. It's one of the most common plays in baseball — a ground ball down the third base line fielded cleanly and thrown across the diamond.

A 3-1 putout works the same way in reverse: the first baseman (3) fields the ball but is pulled off the bag, so the pitcher (1) covers first and receives the throw to record the out. The first baseman gets the assist, the pitcher gets the putout.

What is a 9-3 Putout in Baseball?

A 9-3 putout means the right fielder (9) fields a ball in the outfield and throws the batter out at first base. For this to happen, a few things need to line up — the hitter needs to be slow out of the box or not hustling, the ball needs to be hit hard, and the right fielder needs to be playing shallow enough to make the throw. Throws closer to the foul line have a better chance than throws from the right-center gap.

A 9-3 putout is rare. Coaches generally teach outfielders not to throw to first base because the play almost never results in an out and opens the door for the runner to advance on an errant throw. When it does happen, it's usually a highlight — and the kind of play that earns a defender serious respect in the dugout.

Some of the best 9-3 putouts in MLB history — right fielders throwing out batters at first base.

Frequently Asked Questions