The incident took place in the 33rd over of the Aussie innings when the right-handed Labuschagne went for a reverse sweep on the length ball by Ravichandran Ashwin but failed to find the middle of the bat.
The ball hit the pads of wicketkeeper KL Rahul before it ricocheted onto the stumps. Upon review by the third umpire it was found that no part of Labuschagne’s foot was behind the crease, resulting in his dismissal.
It was Ashwin’s first wicket on his return to ODIs after a hiatus of 18 months.
Earlier, India skipper Rahul, who will lead the team in two of the three ODIs, won the toss and chose to bowl first.
Regular captain Rohit Sharma along with Virat Kohli were rested ahead of the World Cup, which begins next month.
Australian skipper Pat Cummins, who returns after a wrist injury, announced an ODI debut for Matthew Short, who was added to the squad after an injury to Travis Head.