Novak Djokovic continued his bid for a record-extending 11th Australian Open title with a confident win over American 12th seed Taylor Fritz.

The Serb, seeking a 25th major to move past Margaret Court's tally of 24 Grand Slams, won 7-6 (7-3) 4-6 6-2 6-3 in hot conditions to reach the semi-finals.

Top seed Djokovic, 36, has won his past 33 singles matches at Melbourne Park.

He will play either Italian fourth seed Jannik Sinner or Russian fifth seed Andrey Rublev for a place in the final.

Their quarter-final is not likely to finish until the early hours of Wednesday morning after the night session was pushed back to 21:00 local time.

With the singles matches on Rod Laver Arena not starting until 13:00, Coco Gauff's win against Marta Kostyuk in the women's quarter-finals took more than three hours before Djokovic needed almost four hours to beat Fritz.

Sinner and Rublev still have to wait for defending women's champion Aryna Sabalenka's match against Barbora Krejcikova to be completed before they can go on court.

They will, however, at least have an extra day to recover, with the men's semi-finals taking place on Friday.

Djokovic keeps focus to come through

Djokovic calls the Australian Open his "second home", such has been his dominance over the years, and this was another masterful display as he saw off the latest younger challenger on Rod Laver Arena.

The victory means the Serb's last defeat in Melbourne remains a fourth-round loss against South Korea's Chung Hyeon in 2018.

With the match starting about 17:00 local time in temperatures of 31C, Djokovic coolly created eight break points in the opening set but became increasingly flustered as he was unable to take any of them.

The 24-time major champion - looking overheated, regularly using ice towels and shouting towards his team - was almost punished when the 26-year-old created two set points at 6-5 with a stunning forehand winner down the line.

However, Djokovic - who will extend his lead to three over Rafael Nadal at the top of the men's list of Grand Slam winners - regained his composure to save them and it laid the platform for him to pounce in the tie-break.

Helped by Fritz missing a simple volley for 1-0, Djokovic quickly asserted his authority and wrapped up the opening set after 84 minutes.

The American, who had lost all eight of his previous meetings with Djokovic, responded valiantly.

A break of serve in the first game of the second set, before fighting off seven more break points, enabled Fritz to level the match.

But Fritz started to be hampered by a foot issue and Djokovic, looking strong as the conditions cooled, broke twice to win the third set.

Now completely in control, Djokovic was under little pressure on his serve and when he broke for 4-2 in the fourth, the match looked to be heading towards the conclusion.

Fritz rallied once more, hitting straight back to take Djokovic's serve, but the Serb broke again before serving out strongly.

"Conversion of break points was really poor but I think at the end of the day I managed to break him when it mattered in the third and the fourth set," said Djokovic.

"I upped my game probably mid-way through the third set to the end."