The Mumbai Indians, a five-time IPL-winning side, have been left battered and clueless after a fifth defeat in the ongoing 2026 season, which has pushed them into the bottom half of the table at the halfway mark. On Thursday, Mumbai were thrashed by 103 runs by arch-rivals Chennai Super Kings at home, marking their third defeat of the season at the Wankhede — a first in any IPL edition.
Even amid growing concerns over their campaign slipping away, MI found themselves in the middle of a controversy during the game against CSK, when Shardul Thakur replaced Mitchell Santner as a concussion substitute, despite the latter suffering a shoulder injury.
Santner hurt his shoulder during the 17th over of CSK’s innings, when he made a full-length dive at deep square leg to complete a catch and dismiss Kartik Sharma. He immediately left the field clutching his shoulder, triggering concern in the MI dugout. Even co-owner Akash Ambani appeared worried, gesturing towards the shoulder while speaking to a player. Santner was later spotted in the dressing room with an ice pack strapped to his left shoulder.
With no apparent head injury, questions were raised over how MI were allowed to bring in Shardul as a concussion replacement. The move drew further scrutiny given that the team had already used their Impact Sub option earlier in the match, replacing AM Ghazanfar with Danish Malewar.
Shardul eventually came in after Hardik Pandya’s dismissal in the 13th over but failed to make an impact, scoring just 6 off 12 balls as MI collapsed to 104.
How did MI replace Santner with Shardul as concussion sub?
A concussion is a type of head injury caused by a hit or sudden jolt to the head or body, which makes the brain move quickly inside the skull. This can affect how the brain works for a while.
If a player suffers a concussion or is suspected of having one during a match, the team can request a substitute. The team’s doctor or manager must inform the match referee and explain what happened, along with a medical report. They also need to suggest a replacement who plays a similar role.
The match referee then decides whether to allow the substitute, making sure it doesn’t give the team any unfair advantage.
Now, going back to the definition of a concussion, it is important to note that it does not always require a direct blow to the head. A heavy impact to any part of the body can also cause the brain to move rapidly, leading to concussion-like symptoms such as dizziness or imbalance. Mumbai Indians may have argued along those lines in Santner’s case, presenting his shoulder injury as one that potentially triggered such symptoms, which could explain why the match referee approved Shardul as a like-for-like replacement.
The rules may allow it, but the optics definitely sparked a controversy.
