Nick Kyrgios is vowing to fight through the pain barrier after revealing he'll rely on cortisone to get through the Australian Open.
Australia's big hope is battling a knee injury that led to a quickfire straight-sets loss in his third and final match at last week's Hopman Cup in Perth.
"I'm getting some sort of cortisone thing but it's not an injection," Kyrgios said.
"I'm doing everything I can for it."
The 2015 Open quarter-finalist said beating 14-times grand slam champion Rafael Nadal 4-3 2-4 4-3 4-3 4-3 in a Fast4 exhibition match lasting an hour and three quarters on Monday night was the perfect test for his injury.
"I was starting to feel it a little bit towards the end but I had to test it today," Kyrgios said.
"If I can't play Fast4, then it's not going to be looking great for a best-of-five at a grand slam.
"But I'm really happy with how it pulled up. The level was really, really good.
"I don't think Rafa knows any other way than to go out there and give 100 per cent. So I'm going to take great confidence from that.
"I've still got a couple of treatments with what I'm doing and I think I'm gaining improvement every day."
Kyrgios carried a hip injury into the US Open in September, only to quit his third-round match against Ilya Marchenko.
The 21-year-old world No.14 upped his training during the summer to try to avoid similar setbacks but is now racing the clock to be 100 per cent for his home slam starting next Monday.
"I'm going to lay it all on the line in Melbourne. Whether it hurts or not, I'm going to push it to the limit," Kyrgios said.
Two-time Open finalist Pat Cash says Kyrgios must blow his early-round opponents away if he's any chance of breaking Australia's 41-year men's title drought in Melbourne.
"I've always felt that to have success in a slam you need a bit of luck and if Nick's got a niggling injury he wants to get through the first rounds as quickly as he possibly can," Cash said.
"A long five-set match can make life tricky."
Cash said a key to the success and longevity of four-time champion and former world No.1 Roger Federer was his ability to blitz early-round opponents.
"He's got the sort of game that can blow players away and Nick is developing it," he said.
"Getting through the early matches quickly is going to be a big advantage to someone like Nick if he's carrying a injury."
Cash himself carried a shoulder injury into the 1987 final, losing in five sets to Swede Stefan Edberg.
"I always say this is the one that got away," the 51-year-old said.