Steve Smith suffered a rare lapse in concentration just before lunch on day two, with the SCG crowd becoming a factor for the Australian superstar.
The 35-year-old was in the midst of another quality innings against India, settling things down for the hosts after an early collapse that saw three wickets fall.
Smith had built a solid partnership with Beau Webster and the pair looked set to survive until lunch – but Indian seamer Prasidh Krishna had other ideas.
FOLLOW LIVE: Australia vs India fifth Test, day two
Just minutes before the break, Smith edged a delivery from Krishna safely into the hands of KL Rahul in the slips, marking another wicket caught behind the stumps.
Steve Smith walks off after being caught against India. Fox Cricket
"It's come from nowhere," Michael Vaughan said on Fox Cricket.
"You can tell from the reaction from Steve Smith, maybe it was just a switch off in concentration. I just think he switched off. He just loses his balance."
Smith trudged off the ground in disappointment for 33, five runs shy of reaching a rare career milestone of 10,000 Test runs alongside only three other Australians. Â
Replays after the dismissal showed Smith had been agitated by movement above the sightscreen, with members of the crowd standing up and walking.
Steve Smith tells fans to sit down. Fox Cricket
"Just before that ball, he was looking up at the back of the sightscreen and saying 'sit down' and he looked to be a bit annoyed," commentator Brendon Julian said.
"Just before he bowled that, he gestured behind the sightscreen … I just wonder if that's the second lapse in concentration. You get distracted by so much other stuff going on."
It's not the first time Smith has been bothered by things in the crowd in Sydney.
Last summer, the right-hander halted play due to a piece of tape on the sightscreen that was distracting him at the crease.