Dubbed in the Australian press as world cricket's most controversial figure, Harbhajan said he had clearly won the battle of the minds after helping India to a 2-0 whitewash of Australia in the best-of-three ODI finals.
He said crowd abuse and sledging from the Australian cricketers had backfired in spectacular fashion.
"I was too mentally tough for the Australians," Harbhajan told Sydney's The Daily Telegraph newspaper.
"I was proud of the way our team played and I believe we have the potential to be the number one side in the world."
Harbhajan, who had a running battle during the Test and one-day series with Australians Matthew Hayden and Andrew Symonds, said the explosive Australian summer had not affected him.
"What made (Hayden) say all that -- he thinks he is becoming bigger than me and bigger than the game," he told The Sydney Morning Herald, referring to Hayden's "little obnoxious weed" comment aimed at him on radio last week.
"I could have said a lot of things about him but I won't talk about these things in public, we have shown things on the field.
"The best way is to do it out on the ground and we have dominated them, not the other way around.
"We were prepared for any situation or any challenge. We are a very, very proud cricket team. We deserved this. This win takes us to the next level, and we have shown the world what we are capable of.
"We have always given Australia a tough time, a very hard time. We never give them an easy sort of win, we're the only team that does really well against Australia.
"I don't really feel the pressure. I just take it the way things come and I try to stay very cool. What people were saying about me -- I am not here to make friends, and I can't play soft."
Skipper M.S. Dhoni said his team and Harbhajan, in particular, had been vilified and unfairly targeted in Australia.
"He (Harbhajan) became a Michael Jackson sort of personality," Dhoni said before the team's departure home.
"I don't know what will happen to the Australian media without Bhaji (Harbhajan). He was always there on the front page.
"The more he was taken into these controversies, the more determined he was to perform, as skipper it's difficult to calm him down, he's an aggressive player and quite expressive on the field.
"But he's the kind of player who fights hard - that's a quality and that's what character is all about. People might see he might have crossed the barrier but nothing was proved against him."