What Does LOB Mean in Baseball? Explained

By Emma Wilson · January 29, 2028

In baseball, ‘LOB’ stands for ‘Left On Base,’ a statistic that measures the number of baserunners who did not score before the inning ended. It is a key indicator of offensive inefficiency and situational hitting.

Understanding LOB in Baseball

LOB, or “Left On Base,” refers to the total number of runners a team leaves on base at the end of an inning without scoring. This metric is tracked per game, per inning, and over full seasons. High LOB totals often suggest missed scoring opportunities, even if a team gets many runners on base.

Why LOB Matters

Reflects a team’s ability to capitalize on offensive chances
Highlights clutch hitting (or lack thereof) with runners in scoring position
Used by analysts to evaluate pitcher effectiveness in escaping jams
Helps explain discrepancies between expected and actual runs scored

How LOB Is Calculated

LOB is not derived from a complex formula but is recorded manually by official scorers. At the end of each half-inning, any runner still on base who does not score is counted toward the LOB total. The cumulative LOB for a game is the sum of all such instances.

For example, if a team has two runners reach base in the first inning but neither scores, LOB increases by 2. If three more are left in the second inning, the running total becomes 5.

Key Rules in LOB Tracking

Only runners already on base when the third out is made count toward LOB
Runners who score on errors or wild pitches are not counted as LOB
Home runs are excluded since the batter and any runners score
LOB resets to zero at the start of each new inning

LOB and Team Performance Analysis

Teams with consistently high LOB numbers may struggle with run production despite solid on-base performance. Conversely, teams with low LOB totals are often efficient at driving in runs, especially in high-leverage situations.

Advanced metrics like RE24 (Run Expectancy Based on 24 Base-Out States) incorporate LOB data to assess player impact in context.

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Team	Season	LOB (Total)	Runs Scored
New York Yankees	1,376	808	.322
Atlanta Braves	1,321	798	.318
Detroit Tigers	1,389	711	.309
San Diego Padres	1,298	762	.311
Chicago Cubs	1,403	673	.305

Table data source:1, 2

The data shows a trend where higher LOB totals correlate with lower run production, even when on-base percentages are similar. For instance, the Chicago Cubs left the most runners on base (1,403) and scored the fewest runs among these teams (673), indicating poor execution in scoring situations. In contrast, the Yankees and Braves combined strong on-base skills with relatively efficient run scoring despite high LOB counts.

Common Questions About LOB in Baseball

What does LOB mean in a baseball box score?

In a box score, LOB indicates the total number of baserunners a team left on base during the game. It’s typically listed at the bottom of the scoreline and summarizes offensive inefficiency.

Is a high LOB good or bad in baseball?

A high LOB total is generally negative, as it means a team failed to convert base runners into runs. However, it can also reflect frequent baserunners, so context matters.

Does LOB include the batter who makes the last out?

No. LOB only counts runners already on base when the third out is recorded. The batter making the last out is not included unless they reach base safely before the inning ends.

Can individual players have LOB stats?

No, LOB is a team statistic. However, players can be charged with “leaving runners in scoring position” when their at-bat results in the third out with runners on second or third.

How does LOB affect a pitcher’s performance evaluation?

While pitchers don’t directly control LOB, a high strand rate (percentage of inherited runners who don’t score) reflects skill in escaping jams. Pitchers with high LOB rates may benefit from strong defensive support or luck.