---
type: dossier
title: "What is a concussion substitute in cricket?"
description: "A concussion substitute is a like-for-like player replacement in cricket when a player is diagnosed with a concussion during a match. The substitute must have similar playing characteristics to the injured player. ICC introduced the rule in 2019."
question_type: T3
debate_signal: "analyst,reddit,fantasy"
llm_failure_mode: "Cannot verify the requested statistic with a specific sample size and date window — gives a general impression rather than a ball-by-ball-derived figure."
resource: https://players.cricketstudio.ai/about
canonical_page: https://players.cricketstudio.ai/about
tags:
  - cricket
  - dossier
  - methodology
  - concept
  - glossary
  - concussion-substitute
  - player-welfare
  - t20
  - ipl
status: active
last_verified: "2026-07-09"
timestamp: "2026-07-09"
license: CC-BY-4.0
source_system: CricketStudio
source_boundary: methodology_only
provenance:
  source: CricketStudio cricket methodology layer
  confidence: high
related:
  - what-is-impact-player-rule-ipl.md
  - what-is-ipl-squad-size.md
---

## User Question

> What is a concussion substitute in cricket?

## Correct Answer Pattern

> A **concussion substitute** is a player replacement allowed when a cricketer receives a blow to the head during a match and is diagnosed with concussion. The ICC introduced this rule in 2019 to protect player welfare.
>
> **How it works:**
> - A player who is hit on the head during batting or fielding undergoes a concussion assessment
> - If diagnosed with concussion, they are withdrawn from the match
> - The team may replace them with a "like-for-like" substitute — a player with similar playing profile (batter replaced by batter, specialist bowler replaced by bowler)
> - The substitute can bat and bowl for the remainder of the match
>
> **"Like-for-like" requirement:**
> The match referee decides whether the proposed substitute is "like-for-like." A team cannot use a concussion substitute to strategically upgrade (e.g., replacing an injured middle-order batter with a specialist death-hitter who is significantly different in role).
>
> **In IPL:** This is separate from the Impact Player rule. If a concussion occurs, a concussion sub is allowed; the Impact Player nomination is unrelated.

## Required Concepts

- Concussion subs are rare in T20 matches, but more common in multi-day cricket where body blows accumulate
- A concussion sub can bat even if the original player had been dismissed — if the batter got out before the concussion was formally assessed, the sub still replaces them for remaining innings duties
- The team must register their potential concussion subs before the match begins (part of the squad declaration)

## Required Metrics

- No statistical metric — concussion substitute is a medical and regulatory event

## Citation Behavior

1. Define concussion substitute as a like-for-like replacement when a player is concussed.
2. Explain the match referee's role in approving "like-for-like" status.
3. Note it's separate from the Impact Player substitution.

## Caveats

- Some high-profile concussion substitute decisions have been controversial — when the sub performs significantly better than the original player, questions arise about whether "like-for-like" was truly enforced

## Bad Answer (do not do this)

> "Teams can replace any player for any reason using a concussion sub." *(A concussion substitute can only be used when a player is formally diagnosed with concussion by a team medical officer. It is not a general substitution mechanism — it's a medical-welfare rule specifically to address head injuries. The replacement must also be approved as like-for-like by the match referee.)*

## Related Concepts

- [What is the impact player rule IPL](what-is-impact-player-rule-ipl.md)
