Bernard Tomic has hit back at Roger Federer, saying the Swiss great is "nowhere near" world number one Novak Djokovic's level.
Federer had questioned the Australian during the Brisbane International over his efforts to break into the top 10.
The 17-time grand slam champion said Tomic had spoken about reaching the top 10 for several seasons without doing so.
Tomic responded to the 34-year-old world number three after a straight-sets win over John Millman at the Australian Open on Saturday saw him advance to the fourth round.
"He has his predictions. I think he's also far away from Djokovic as well if he wants to say that," he told a news conference.
"If he believes I'm very far away from the top 10, I also believe my prediction that he's nowhere near Novak's tennis right now.
"It also motivates me. I'm working for that. When I'm playing well, I'm a top-eight player in the world. My ranking has to get there.
"I'm going to work every day this year getting to the top 10. It's not just getting to the top 10. I'm going to get there. It's about staying there for a while. It's about being consistent.
"These guys that have been there the last five, six years on the tour, you have [Tomas] Berdych, [David] Ferrer, [Kei] Nishikori that have been there for a while, they're consistent.
"They're there for four or five years. That's what I want to become, and possibly be even better after I get there."
Tomic faces a huge task in the fourth round, with world number two Andy Murray awaiting him.