Marat Safin [Images] moved into the third round of the Australian Open on Wednesday before offering younger sister Dinara some brotherly advice -- grow up.

The fourth seed swiftly bludgeoned his way past Czech Bohdan Ulihrach with a 6-4, 6-1, 6-3 win before turning his sights on his sister.

Safina, who won the first set against second seed Amelie Mauresmo before succumbing in three, must work harder if she's to compete at the top, Safin said.

"She has to make a lot of changes to be able to compete with all these kind of players.

"And to be able to do that, she needs to have a character and she needs to be a little bit of a grown-up woman.

"Of course, she is little bit young (18), and I know everything everybody is saying to her, 'she is still young, she has big future in front of her.'

"But I'm sorry, if you don't really understand yourself what's going on, it's a little bit difficult for somebody to fix it and explain it.

"Nobody's going to tell her what to do, she has to decide for herself, you know? It's my duty to help her, but if she doesn't want to listen..."

World number 44 Safina reached the third round in Melbourne last year, but though she has won two WTA Tour titles and has been ranked as high as 29, Safin said she should follow the example of her more illustrious and higher-ranked compatriots.

"She has to grow up, be a little bit responsible for the things that she is doing and the decisions that she is taking," he said.

"For some reason she cannot make any decisions; she needs somebody to explain her everything.

"It's a little bit sad to watch because I can see that she has great potential. She has a game, but she doesn't have this character like (Maria) Sharapova has and (Svetlana) Kuznetsova, (Elena) Dementieva, (Anastasia) Myskina, all the Russian girls.

"They're great players. What they are good at is that they have a character of fighters, of wanting to achieve something."

Safin also said he would not be playing mixed doubles with his sister at any time in the foreseeable future.

"There is no more charity for my sister. She has to learn the hard way. I think it's the way that everybody understands, I guess.

"(There is) no hard feeling. Of course, she's my sister.

"It's just a little bit sad to see, to watch the train pass. And then she has to run away when I told her already 'take this train, you know, like before it's gonna be too late.'"

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