Former world number one Lleyton Hewitt said the brilliance of Roger Federer over the past few years has forced him to change his game in a bid to match the Swiss.
The Australian, runner-up in 2005, is bidding to become the first home winner of the men's singles at the Australian Open since Mark Edmondson in 1976.
Under the tutelage of his new coach Tony Roche, the world number 21 has been working on becoming more aggressive in a bid to get back into the top 10 and try to add to his two grand-slam titles.
"The game's always changing," Hewitt told reporters on Sunday.
"Roger Federer's obviously the guy that's taken the game to a new level. You've got to look at little ways of improving your game to be able to match it with the best players.
"And being slightly a bit more aggressive and maybe not so predictable is maybe one way of doing that."
Hewitt's former Davis Cup team mate Wayne Arthurs suggested in the Australian press on Sunday that the efforts to become more aggressive may have cost him the consistency that helped him reach the top.
Early defeats in the warm-up events in Adelaide and Sydney suggested he may be struggling to find the balance, but Hewitt said he was still tough to beat.
"I'm still pretty consistent, though, compared to most guys out there, still play the percentages a lot better than most guys out there," he said.
Hewitt begins his campaign against Belgian Steve Darcis, while he could play former champion Marat Safin or 2006 runner-up Marcos Baghdatis in the third round.
The Australian said he was just focusing on his first-round match but said he still believed he could win the title.
"Every year (he doesn't win) is another year down the drain, I guess," he said.
"(But) I'm only 26 at the moment. The body's been feeling really good the last couple of months. You need a little bit of luck in any grand slam to win it.
"For me right at the moment, it's just a matter of trying to survive the first week. If I put myself in a position deep in the second week, I've got as good a chance as anyone."
(Editing by John O'Brien)