During the IPL 2026 match between Mumbai Indians (MI) and Chennai Super Kings (CSK) on April 23, MI's decision to substitute Shardul Thakur for Mitchell Santner as a concussion replacement has ignited controversy. Santner sustained a shoulder injury while attempting a catch, yet MI utilized the concussion substitution rule, which is intended for confirmed or suspected concussions. This decision raised questions among fans regarding the legitimacy of the substitution and whether it was a tactical maneuver. Critics on social media expressed frustration, arguing that Santner's injury did not qualify under the concussion rules, leading to calls for clearer guidelines on injury replacements in the IPL. Despite the controversy, the match concluded with MI suffering their largest defeat in IPL history, losing by 103 runs, as CSK scored 207/6 with Sanju Samson contributing an unbeaten 101 runs.