Marnus Labuschagne carried on batting despite copping a heavy hit to his helmet from Indian fast-bowling debutant Mohammed Siraj.
The Australian number three badly misjudged a short ball from the Indian quick, looking to play a shot but not quite reading either the pace or the bounce of Siraj’s delivery.
'ALMOST DISASTER': Cricket fans hail chaotically superb moment
REST IN PEACE: Cricket world mourns death of English icon
Labuschagne didn’t appear to be rattled by the blow, able to withstand the heavy impact to his helmet without falling to the ground or stumbling.
He then took several minutes to be assessed by a team doctor, while play was further delayed as a replacement helmet at Labuschagne transferred the lining from the old helmet into the new one.
India initially appealed for a catch, but replays soon showed the ball had thudded off the Australian number three’s helmet.
While several batsman, including Test hopeful Will Pucovski, had come off second best after being hit on the helmet in the domestic competition, former Test batsman Michael Slater said Labuschagne’s helmet had done its job to protect him.
— News Cricket (@NewsCorpCricket) December 26, 2020
“A glance would’ve gone over slips and keeper. That’s hit him heavily. He has to be assessed and now he’s got his opportunity to go through the concussion tests,” Slater said on commentary for Channel 7.
“But that helmet will need to be changed. Because the view is, as a batsman, and those who make the helmets, that has done its job for him - it’s taken the impact.
“That (impact) makes slight little fractures when that ball hits so hard and if it was to hit the same spot again, 70% chance the ball will go straight through, so that helmet needs to be changed.”
While Labuschagne was able to shake off the short ball, the Indian side got their man a short time later, with fellow Test debutant Shubman Gill taking a sharp catch off the bowling off Siraj a short time later to dismiss him for 48.
India in control thanks to sharp bowling
The dismissal left young allrounder Cameron Green (6 not out) and captain Tim Paine (0 no) at the crease.
Labuschagne combined with Travis Head (38) for a 86-run fourth-wicket stand, before stand-in India captain Ajinkya Rahane took a catch off quick Jasprit Bumrah's bowling.
The MCG pitch has been infamously flat in recent years, but India's bowlers were able to extract early seam and spin from it.
Bumrah (2-24) cleaned up Burns in the fourth over, before Ravi Ashwin (2-25) claimed Matthew Wade and the prized scalp of Smith.
The stage was set for another Smith masterpiece when he entered the crease at 2-35, but the world's No.1 Test-ranked batsman was quickly sent packing.
Smith was caught at leg-slip off a turning Ashwin delivery without scoring - the 31-year-old's first Test duck since 2016.
It was not the only nought of the morning, with Burns' 10-ball stay again putting him under pressure to keep his Test place.
Bumrah had Burns nicking to recalled wicketkeeper Rishabh Pant - with the Queenslander now averaging just 24.2 from his last nine Test innings since making 97 against Pakistan in November 2019.
With star opener David Warner expected to be fit for the next Test, Burns likely needs a big second innings score to save his international career.
Attacking makeshift opener Wade went for one big shot too many and was caught by a diving Ravindra Jadeja off Ashwin's bowling for 30.
Click here to sign up to our newsletter for all the latest and breaking stories from Australia and around the world.