Inherited Runners ScoredIRS
IRS stands for inherited runners scored in baseball. Runners who were already on base when a reliever entered and went on to score after he took over.
How IRS is calculated
Counted; the run goes on the previous pitcher’s ledger, not the new one’s.
The share that scores is the honest measure of a relief ace. League-wide about 30% of inherited runners score.
What counts as a good IRS?
Half of the 130 qualified MLB players in 2026 were at or below 8. The best tenth were under 4.
- Median
- 8
- Top 10% (low)
- 4
- Leader
- 1
Qualified: 20+ IR, non-zero, 2026 regular season.