Novak Djokovic reached a major milestone Monday as he began his quest for a record-extending eighth Australian Open title with a 7-6 (5), 6-2, 2-6, 6-1 win over Germany's Jan-Lennard Struff in Melbourne.

The second-seeded Serbian fired 44 winners and became the sixth man to reach 900 tour-level victories, joining Guillermo Vilas, Rafael Nadal, Ivan Lendl, Roger Federer and Jimmy Connors.

"I am just starting," Djokovic joked. "I am obviously very proud of all the achievements, but at the same time I try to remind myself of how grateful I have to be, still playing on a very high level the sport that I truly love."

Djokovic dropped his serve four times before finding his rhythm and putting away Struff in two hours and 16 minutes.

"Credit to him for fighting," Djokovic said. "He is a very powerful player who brings a lot of strength in his shots on the court. Congratulations for a great match to him."

Djokovic, the defending champion, reached the second round for the 14th consecutive year and will face either Japan's Tatsuma Ito or India's Prajnesh Gunneswaran. It will be the 16-time Grand Slam winner's first meeting with either player.

The third-seeded Federer tallied 11 aces and 34 winners and saved the only break point he faced in a 6-3, 6-2, 6-2 win against Steve Johnson. The 20-time Grand Slam champion awaits the winner between French qualifier Quentin Halys and Serbia's Filip Krajinovic.

Federer improved to 21-0 in first-round matches in Melbourne. The 38-year-old Swiss star hasn't lost an opening match at a Grand Slam since the 2003 French Open.

Monday's biggest upset winner was Hungary's Marton Fucsovics, who eliminated 13th-seeded Canadian Denis Shapovalov 6-3, 6-7 (7), 6-1, 7-6 (3). Shapovalov finished with 38 winners and 62 unforced errors. Sam Querrey beat No. 25 seed Borna Coric of Croatia in straight sets, 6-3, 6-4, 6-4.

In other opening-round action, No. 30 seed Daniel Evans of Great Britain rallied from two sets down for a 3-6, 4-6, 6-1, 6-2, 6-3 win against Mackenzie McDonald. Evans' next opponent is Japan's Yoshihito Nishioka, a 6-4, 3-6, 6-2, 7-6 (1) winner against Serbia's Laslo Djere.

Other seeds advancing to the second round included No. 6 Stefanos Tsitsipas of Greece, No. 8 Matteo Berrettini of Italy, No. 18 Grigor Dimitrov of Bulgaria and No. 22 Guido Pella of Argentina.