He was facing his first ball of the innings and was trying to duck under the bouncer when he was hit on the back of the head.

While Sarfaraz continued to bat, facing 22 balls for 14 runs, he looked unwell and a while later walked off the field.

Sarfaraz was substituted under the International Cricket Council’s Concussion Rule introduced in all formats of men and women’s international cricket and for first-class cricket as well.

What is ICC’s Concussion Rule

The rule came into effect from 1 August, 2019 according to which the ICC allowed like-for-like concussion substitutes in case a player got hit on the head.

A like-for-like substitute means a batter must be brought if the concussed player is a batsman.

The officials in cricket traditionally allowed teams to have a substitute if a player was injured for any reason. However, that sub cannot do anything other than field.

Under the concussion substitute ruling, the sub can bat, bowl and field and this is the crucial point to the new ruling.

“Teams will have the option of replacing a player who has sustained a head or neck injury during an international match and has subsequently been diagnosed with concussion or suspected concussion,” the ICC rule states.

According to ICC Concussion Management Guidelines the diagnosis of concussion is clear in case of confirmed loss of consciousness; suspected loss of consciousness (prolonged immobility for more than 5 seconds); seizure; convulsion or tonic posturing (stiffening of any limb); ataxia, loss of motor control, inability to stand or staggering; dazed or blank stare; or the player in a confused state, disoriented or with memory impairment.

Australia’s Marnus Labuschagne was the first ever concussion substitute who deputised for Steve Smith at Lord’s in 2019. Smith had been hit by a Jofra Archer bouncer and subsequently left the game.

Before Sarfaraz Ahmed’s replacement with Muhammad Rizwan in the ongoing test, Pakistan has before used the concussion rule.

Earlier this year, Kamran Ghulam was brought in as a substitute for Haris Sohail after he was hit by a Lockie Ferguson bouncer in the third ODI against New Zealand.