Injuries · GWTTKB Research

When a starter is ruled out, his position-mates beat their own average by a measurable amount

Measured against a control group. In no-vacancy weeks the same players sit at roughly zero, which is what makes the effect real rather than noise.

GWTTKB Research · updated 2026-08-16
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The question

How much do fantasy players gain when a starter is ruled out?

What the field generally says

That backups gain when a starter sits is obvious. What is almost never published is the size of the gain, by position, against a control.

What we measured

When a genuine starter is ruled out, his position-mates beat their own trailing five-game average by a clear margin — largest at running back, smallest at wide receiver. The control is the important half: in weeks with no vacancy, the same players sit at roughly zero against their own trailing average, so this is not simply players sometimes beating their mean.

PositionExcess PPR vs own averageControl (no vacancy)Treatment weeksWelch t
RB+3.18-0.094669.43
QB+3.13-0.06983.75
TE+1.480.153025.01
WR+1.22-0.231,6226.72

Why it comes out that way

The running back figure is more than double the receiver figure, and that is the same structural fact that shows up in the handcuff data: back touches funnel to one replacement while receiver targets disperse across a room.

How it was tested

Starter defined before the event, not after. Treatment weeks are those where a genuine starter is ruled Out; control weeks are the same players in weeks with no vacancy. Each player is measured against his own trailing five-game average, so a good player is not credited for being good. Welch t-statistics reported alongside.

Figures on this page are read at build time from the same data file the site’s projections use.

What this does not say

This is the average across all such events, and the spread around it is wide. It tells you the expected size of the bump, not that any specific backup will get it.

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