In a blockbuster Australian Open warm-up meeting between the two former world number ones, it was 21-time Grand Slam champion Djokovic who shot out of the blocks quickest, as he surged to a 4-2 lead in the opening set.

Djokovic was in some discomfort in the seventh game after hyper-extending his left hamstring while stretching to make a forehand, but he soldiered on and pulled off an exquisite lob before taking a medical timeout for treatment.

The Serb claimed the opening set and raised his game at 3-3 in the next by producing a blistering return and a smooth pass at the net before Medvedev surrendered his serve with a double fault on breakpoint.

Djokovic saved a break point with a 200 km/h second serve before holding firm from there to seal a comfortable victory.

"Thankfully it was nothing too serious," Djokovic said of his injury in an on-court interview. "If it was I wouldn't be able to continue. I took anti-inflammatory (medication) and settled in.

"I was trying to keep the momentum going and not allow him to break my serve. That was the key. Eventually, I would get a chance. The longer the match went on, my hamstring got warmer and bothered me less.

"Hopefully for tomorrow, it'll be fine."

The January 16th-29th Australian Open will be without world number one Carlos Alcaraz (19) following his leg injury and the organisers of the Melbourne Park major would have endured tense moments after nine-time champion Djokovic clutched his leg.

"For me at this level, at this stage of my career and my life after quite a few years of professional tennis, every match counts and every match is a present in a way," Djokovic said.

"I try to give my best and win wherever I am."

Up next for Djokovic is Korda, who reached the final after Japan's Yoshihito Nishioka (27) retired due to an injury with the score at 7-6(5) 1-0.