Cameron Green added to Australia's list of injury concerns when he was struck on the side of the head by a fierce straight drive from Jasprit Bumrah on the opening day of the pink-all warm-up match at the SCG.
It was later confirmed that he was subbed out of the match under the concussion protocol and replaced by Patrick Rowe but had been cleared of any fractures.
Pip Inge, Cricket Australia team doctor, said: "Cameron sustained a mild concussion while bowling for Australia A. This is Cameron's first concussion. He has returned to the team hotel and will not play the remaining two days of the tour match.
"We will continue to monitor him and provide an update on his condition in due course."
Bowling the first delivery of his seventh over - in his second spell of the day - Green took the ball on the side of his head in his follow through as it burst through his hands.
He immediately went to ground and the umpires called for medical staff straightaway with the India batsmen quickly showing concern. By the time the physios and doctor had made it to the middle Green was on his feet but after a short assessment left the ground.
Green's blow follows the hit to the helmet suffered by Will Pucovski in the previous warm-up match at Drummoyne Oval which left him with mild concussion and in doubt for the opening Test. Australia are already without David Warner for at least the Adelaide match due to his groin injury.
Green was pushing his claims for a Test debut having made a century and taken two wickets in the first Australia A game following a strong start to the season in the Sheffield Shield. He is still limited to four-over spells as he returns from stress fractures of the bat but his batting alone makes a strong case for selection.
He had earlier produced an excellent delivery to have Shubman Gill during his first spell.