R Ashwin has come down hard on the Australian crowds, especially the ones in Sydney, who according to him have dished out "nasty" abuse even on his previous visits to the country. During the ongoing Test, Ashwin said, they crossed a line and hurled racial abuse at Mohammed Siraj. India lodged an official complaint with the match officials on the third evening, but there was an incident on the fourth day too, which led to a group of spectators being evicted from the stadium.

"This is my fourth tour to Australia and in Sydney, especially, we have had a few experiences even in the past. I think one or two times even the players have reacted and got into trouble in the past, and that's not because of the player, it is actually because of the way the crowd has been speaking, especially the people close to the boundary edge."

Ashwin was probably referring an incident on India's 2011-12 tour of Australia, when Virat Kohli was photographed gesturing inappropriately to the crowd at the SCG and was pulled up for it. Ashwin said such behaviour from spectators needed to be dealt with harshly.

"They have been quite nasty, they have been hurling abuses as well, but this is the time they have gone one step ahead and used racial abuse," Ashwin said. "There was an official complaint lodged yesterday, and the umpires also mentioned it to us that we must bring it to their notice as soon as it happens, on the field, and then they will be able to take action.

"It is definitely not acceptable in this day and age. We have seen a lot, right? We have evolved as a society. This must be definitely dealt with an iron fist. And we must make sure that it doesn't happen again."

Ashwin said he was disappointed no one in the stands called out bad behaviour of fellow spectators. "Personally I think Adelaide and Melbourne weren't as bad," he said. "But this has been a continuous thing at Sydney. I have experienced it as well. They do tend to get nasty. I don't know why and for what reason.

"Unless and until it is dealt with, people don't find the reason to look at it in a different way. In fact I was quite surprised that some sections of the crowd continuously did it and they were no mates around them to pull them up for it. It definitely had to be dealt with. Disappointing is a very, very mild word, I must say."

As a young play on his first tour to Australia back in 2011-12, Ashwin said it was shocking for him that a cricketer might have to deal with such crowd abuse. He said it was good that the current younger lot - such as Siraj - were much more aware of what is fine and what is not.

"If I go back to the first tour in 2011-12, I had no clue what racial abuse is or how you can be made to feel small in front of so many people," Ashwin said. "And people actually laugh at you when you get abused. There is another set of people just enjoying it. I had no idea what this was at all. Whenever you stood at the boundary line, you wanted to run in 10 yards to avoid these things.

"As things have strode on, and we have learned more and more on tours, this is definitely not acceptable. Even yesterday when Siraj brought it up, Ajinkya, myself and Rohit got together and went to the umpire and did report it. Nowadays the boys are better equipped and aware. Even Siraj, who is new, does know that this is the line you cannot cross. It is a wonderful thing. It must be met with the way it was met."

Sidharth Monga is an assistant editor at ESPNcricinfo