Novak Djokovic found his form at the Australian Open in a straightforward win over Tomas Martin Etcheverry.

The 10-time champion has been struggling with illness and was well short of his best in his first two matches, particularly a second-round clash with Alexei Popyrin on Wednesday that he was lucky to escape.

But Djokovic, playing his 100th match at Melbourne Park, looked much more like his usual self in a 6-3 6-3 7-6 (2) victory over Argentina’s Etcheverry, who beat Andy Murray in the first round.

The Serbian was hitting his groundstrokes with their customary ferocity again and, although there were perhaps still a few more mistakes than he would have liked, he was always fully in control of his 92nd win on these grounds.

Djokovic said: “It was a great match, the best performance I had during this tournament. I’m pleased with the way I played throughout the entire match, particularly the first two sets.”

The form players of the first week have been fourth seed Jannik Sinner and big home hope Alex De Minaur.

Sinner finished last season beating Djokovic twice in one day as he led Italy to the Davis Cup title and has eased through to the fourth round here.

He dropped just four games in a 6-0 6-1 6-3 destruction of Sebastian Baez to set up a meeting with Russian Karen Khachanov, who was a semi-finalist here last year.

Sinner said: “Today’s match was really good. I played good tennis. I love the conditions also today, because was no wind and no sun.

“I felt great… I made the right decisions and I used every chance I had today, which maybe in the first match I was struggling a little bit. But it’s good to have this match feeling back again. I’m very excited to step on the court every time.

“I’m doing my job. I try to stay focused. I try to find a solution against every player I play. The next round is going to be different, it’s going to be tough.”

Khachanov, who has reached at least the quarter-finals at three of his last four slams, had a tougher time in beating Tomas Machac 6-4 7-6 (4) 4-6 7-6 (5).

De Minaur’s rise into the top 10 just before the tournament fuelled hopes of a first home winner of the men’s singles since Mark Edmondson in 1976, and he has dealt with the pressure immaculately so far.

The 24-year-old had no trouble getting past Italian qualifier Flavio Cobolli, dropping only seven games in a 6-3 6-3 6-1 victory.

Last year’s runner-up Stefanos Tsitsipas also had a comfortable afternoon, beating young Frenchman Luca Van Assche 6-3 6-0 6-4 to set up a clash with American 12th seed Taylor Fritz, who came from a set down to see off Fabian Marozsan 3-6 6-4 6-2 6-2.

America's J.J. Wolf was the top seed in action on Tuesday at the Houston Open and he had no issue in his 6-3 6-2 first-round victory over Jordan Thompson.

Wolf, the fifth seed at the United States' only clay court event on the ATP Tour calendar, needed just 75 minutes to send the Australian home early on the back of a rock-solid serving performance.

Thompson was not able to produce a single break point opportunity in the match, and Wolf left an exclamation point on the contest by winning the final five games to run away with the win.

Meanwhile, seventh seed Marcos Giron gave the American crowd another win to cheer for in his 6-0 6-2 demolition of Ecuador's Emilio Gomez.

The chance for the double-bagel was there for Giron after winning the first 11 games to race out to a 6-0 5-0 lead, but he blew four match points as Gomez showed no quit and secured a break to at least take the match over the 60-minute mark.

Eighth seed Tomas Martin Etcheverry prevailed 6-3 6-4 in his all-Argentine clash against Juan Manuel Cerundolo, taking a 3-2 lead in their overall head-to-head meetings after rising 21-year-old Cerundolo took the past two.

German qualifier Yannick Hanfmann booked a second-round matchup against second seed Tommy Paul after a hard-fought 6-4 3-6 6-2 triumph over Japan's Yosuke Watanuki, while Chile's Cristian Garin had little resistance in his 6-3 6-0 victory in a South American showdown against Bolivia's Hugo Dellien.

In the late window, Jack Sock failed to complete the United States clean sweep for the day as he fell 6-2 6-4 to the Czech Republic's Tomas Machac.