After sitting out most of 2017 tennis season with a career-threatening injury, former World No.1 Novak Djokovic has spent the last six months reassessing his serving technique.
"It was an obvious part of my game that I had to address because of my elbow issues," the Serbian said on Saturday, reports Xinhua news agency.
"Although it's not entirely different... even those small changes have made a lot of difference," he said.
The six-time Australian Open winner enlisted the help of tennis great Andre Agassi and power hitter Andy Roddick, to find a way to help release the "load from the elbow".
"There are three or four details that I have changed," Djokovic said.
"The correction and improvements to the service are allowing me to be more efficient and spend less energy," he said. "So I'm really looking forward to trying out my new server!"
Although the time off has given Djokovic time to heal up for the 2018 season, questions still remain about whether the 30-year-old Serb can return to the same kind of form that saw him claim 12 Grand Slam singles titles.
Djokovic admitted, the injury is "still not 100 percent" healed and that he still feels "some pain".
"Even if it was 100 percent healed, after six months out of competition, you never know how you are going to react," he said.
"After long, very thorough consultations with my team and doctors, we have made the decision that it is fine and adequate to play," he added.
The first test will come on Tuesday, against the 14th seed of the 2018 Australian Open, American Donald Young, in what is likely to be an extremely hard fought contest.