Team India physio Nitin Patel came on to the field and Saini left the ground after doing some stretches. Rohit Sharma bowled the final delivery to complete the over.
"Navdeep Saini has complained of pain in his groin. He is currently being monitored by the BCCI medical team," BCCI said in a statement after the incident.
"Navdeep Saini has now gone for scans," it said in the next update in the last session.
UPDATE - Navdeep Saini has now gone for scans.#AUSvIND https://t.co/pN01PVnFfx
— BCCI (@BCCI) January 15, 2021
India was already forced to make four changes to their Playing XI which last featured in the third Test in Sydney.
Jasprit Bumrah, Ravichandran Ashwin, Ravindra Jadeja, and Hanuman Vihari have been left out due to respective injuries and in their places, T Natarajan, Washington Sundar, Shardul Thakur, and Mayank Agarwal have been brought in.