Former captain Ponting, 36, has struggled with the bat, having hit a barren patch after making 209 in January 2010, and several former cricketers believe the right-hander is past his prime.
Since that game, Ponting has played 16 Tests and scored 797 runs at an average of 27.48, with a top score of 78.
But India spinner Harbhajan, who has been involved in many battles with Ponting over the years, believes the Australian will be back among the runs.
"I do not think Ponting is finished and I think people are making a big mistake by writing him off," said Harbhajan, who has dismissed Ponting more than any other bowler.
"Two years ago, people were saying the same things about Rahul Dravid (who averages 60 from 11 Tests this year) as what they are saying about Ponting now."
"Look what Dravid has done. I am sure Ponting will do the same."
Harbhajan, struggling with form himself and out of the India team for the tour to Australia, also said great players should never be questioned.
"Guys like Ponting, Dravid and (Sachin) Tendulkar know what they are doing and people should stop questioning them. They should respect them for what they have done for the game and they should respect them if they think they can bat on and contribute to cricket," he said.
"The fans in Australia should not put pressure on Ponting, they should just accept he has been given a chance to keep playing and they should get right behind him and support him. Ponting is only one innings away from finding his top form."
Harbhajan believes India have a chance to claim their first series win in Australia: "This Australian side is a lot weaker than sides of the past. There is no Adam Gilchrist or Shane Warne or Glenn McGrath."
"India have definitely got a very good chance to beat them on their home soil. I don't want to predict a scoreline, but I am sure India will do very well."
