There are fresh concerns over the fitness of Novak Djokovic after the Australian Open favourite repeatedly received medical treatment during a practice match against Daniil Medvedev on Wednesday.

Medvedev won the only set they played at Rod Laver Arena, 6-4, with NCA NewsWire reporting that doctors assessed Djokovic's left knee at three consecutive changes of ends and wasn't "moving very well."

Djokovic won the Adelaide International title on Sunday after battling hamstring issues in the semi final victory over Medvedev on Saturday.

The 21-time grand slam champion appeared hampered in Adelaide, clutching at his leg and testing his range of motion several times before beating the Russian.

Medvedev clearly thought Djokovic was feigning the injury on Saturday, mocking his rival by grabbing his left hamstring and hopping around.

Djokovic batted away fears in his on-court interview.

"Thankfully it was nothing too serious," the 35-year-old said.

"If it was I wouldn't be able to continue. So, I just tried with some medical timeout, some inflammatories and kind of settled in...

"The longer the match went the more my hamstring was warmer, I guess, and bothering me less."

Djokovic is scheduled to play against Nick Kyrgios in a sold-out exhibition match on Friday.

The Serbian superstar missed last year's tournament after being deported for not being vaccinated against COVID-19.