Novak Djokovic will debut a new service action at the Australian Open, forced by the former world No.1's elbow complaint.
The 14th seed is a confirmed starter in the first grand slam of the year after months of doubt.
He shut down his 2017 season after Wimbledon due to the injury, only playing his first match back at Kooyong this week.
Djokovic admits his right elbow "hasn't 100 per cent healed" but he's made a judgment call to play at his favourite major in any case.
"Right now it's at the level where I can compete, and every day is getting better," he said.
"I'm hoping that it can be 100 per cent at the start of the tournament. Throughout the tournament, I don't know how it's going to behave.
"Even if it's 100 per cent healed, after six months of no competition, you never know how you're going to react.
"So let's see. There's not much more I can do."
Djokovic, a six-time Open champion, has turned to coaches Andre Agassi and Radek Stepanek for advice on how to adapt from the injury.
On his comeback on the practise courts, Djokovic found the pain worst while serving, but found help close to hand.
Agassi famously adapted his groundstroke and serve when defending his Wimbledon crown in 1993 after a crippling wrist complaint.
"We've talked about that," Djokovic said.
"Both Radek and Andre ... they spent a lot of hours analysing my serve. I did, too.
"There are three, four details, things, that I've changed with my rotation, the elbow up, which is the most obvious one.
"I feel like I spend less energy but I'm more efficient. I'm really looking forward to try out my new serve here."
Djokovic was coy on the precise nature of the injury, saying he was "not going to get into the details" of the either the diagnosis or the treatment.
But he's starting the tournament with medical advice he won't further damage his limb by playing, and hopes to surpass his ordinary 2017 season.
"Even the first part of last year, I did struggle a lot with the performance," he admitted.
"I still know what I'm capable of, and I believe in my own abilities to win against the best players in the world.
"I know that if I get myself to desired level of performance - mental and physical - that I can actually have a good chance to go far in the tournament.
"I'm here. I'm going to play. Hopefully everything goes well."