Controversy erupted on social media during the Indian Premier League (IPL) match between Mumbai Indians and Chennai Super Kings (CSK) after the former named Shardul Thakur as a concussion replacement for Mitchell Santner at the Wankhede Stadium on Thursday night. Although CSK emerged victorious by a whopping 103 runs, the replacement did create a buzz in the El Clasico that saw MS Dhoni and Rohit Sharma missing.
The incident took place on the 17th over of CSK's innings when Santner dived low at the boundary to dismiss Kartik Sharma, in what was a sensational catch. The New Zealand captain landed on the ground in an awkward manner on his left shoulder. He immediately left the ground and was seen with a ice pack on his shoulder.
A close look at the replays showed that Santner's head in fact hit the ground first, while taking the catch.
Did Shardul Thakur qualify as a concussion substitute?
Technically, yes. Thakur does qualify as a concussion substitute in place of Santner since the IPL match referee officially accepted the medical assessment which was submitted by the team's medical staff. Fans, however, were left frustrated with the decision to appoint Shardul Thakur as a concussion sub because of the fact that Santner's injury had more to do with his shoulder rather than a head injury.
Mumbai Indians head coach Mahela Jayawardene cleared the air at the post-match conference in detail. “Santner hit his head first, the neck and obviously, the shoulder as well," said the former Sri Lankan captain.
"He then went for a scan. Once he got back, he was lying down. Yes, the ice was there for the shoulder, but he felt that he wasn't stable, so we took him for a scan in that situation. We requested a concussion sub. It's at the match referee and the umpires' discretion. They allowed Shardul Thakur. It is what it is. But hopefully, Santner's injury isn't too bad. Once he's back, we'll have a look at it,” added Jayawardene.
What does the IPL rules say?
According to the rule 1.2.9.1 of the IPL playing conditions, under ‘concussion replacement’, if a player sustains a concussion or suspected concussion, as a result of a head or neck injury during the course of the relevant match, a Concussion Replacement may be permitted if "the head or neck injury must have been sustained during play and within the playing area". The rule goes onto say that “a concussion or suspected concussion must have been formally diagnosed by the Players’ Medical Team Doctor.”
The rule further adds that the team manager shall submit a Concussion Replacement Request to the IPL Match Referee on a standard form, which will. In the form, the team must formally report the player who has suffered a concussion or suspected concussion, explain when and how the incident happened, and confirm that the team doctor believes the player may have sustained a concussion from that incident.
The team should also name a like-for-like replacement, with the replacement then approved by the match referee. In this case, however, Shardul is not literally a "like-for-like" replacement, since he is a right-arm seam bowling all-rounder compared to Santner's left-arm spin bowling all-rounder, forcing another debate among fans and experts alike.
Despite coming onto bat, Shardul Thakur was only able to score six runs from 12 balls, and Mumbai Indians, looking to chase down 208, where bowled out for just 104 in 19 overs. MI are currently in eighth place in the IPL 2026 standings with just four points from seven matches.
