Novak Djokovic into the fourth round after beating Tomas Martin Etcheverry in 100th Australian Open match

MELBOURNE, Australia (AP) — With 100 matches at the Australian Open and a record 24 titles across the four majors, Novak Djokovic is well placed to judge how he's progressing at a Grand Slam.

And he's starting to feel better about his health and his game after winning in straight sets Friday for the first time this tournament with a 6-3, 6-3, 7-6 (2) victory over Argentina's Tomas Martin Etcheverry.

With it, he improved to 92-8 at Melbourne Park, where he's won the title 10 times and extended his winning streak to 31 matches.

"Coming into the tournament I haven't really felt great health-wise, physically, and also game-wise. It's all connected obviously," Djokovic said in his post-match press conference. "I haven't had a best out of the tournament in terms of the quality of tennis, but I'm in the fourth round.

"I believe that things will progress as the tournament goes on. That's the case tonight and today. Hopefully every day will be better."

Only Roger Federer (117 matches and 102 wins) and Serena Williams (105 matches and 92 wins) have played more matches at the season's first major.

Djokovic has had a virus and been dealing with a sore right wrist. He lost sets in each of the first two rounds against 18-year-old Croatian qualifier Dino Primzic and Alexei Popyrin, when he challenged a heckler to “say that to my face.”

Against Etcheverry, he didn't even face a breakpoint.

Not that No. 30 seed didn't challenge him, really going for his ground strokes and chasing down drop shots—to the point where he had to veer off court to avoid the net in the third set and nearly crashed into the umpire's chair.

As he got closer to victory, Djokovic started to put his index finger to his ear after each winner, urging more support from the crowd.

He closed with a pair of aces and said the win was "the best performance I had during this tournament"—but admitted it was still far off from his own high standards.

"I played better than I did in the first two rounds, so that's a positive change, I guess," Djokovic said. "Starting to feel better game-wise and physically, as well. It's positive signs.

"I still haven't been playing at my best."

The defending champion could be in for a more straightforward battle in the fourth round, where No. 20 seed Adrian Mannarino awaits. The 35-year-old Frenchman pulled off a miracle escape as he toppled No. 16 seed Ben Shelton—spoiling a Djokovic-Shelton US Open rematch in the process—and won 7-6 (4), 1-6, 6-7 (2), 6-3, 6-4 in his third five-setter in a row at the Australian Open.

Tennis.com Staff contributed to this report.