Novak Djokovic's first match with former rival Andy Murray as his coach did not start all that well, even against a 19-year-old making his Grand Slam debut.

Still, after dropping his opening set at the 2025 Australian Open on Monday night to Nishesh Basavareddy, an American who left Stanford University and turned pro last month, Djokovic eventually asserted himself for a 4-6, 6-3, 6-4, 6-2 victory to begin his bid for an 11th championship at Melbourne Park and a record 25th major title overall.

"I'm obviously thrilled to have him in my corner," Djokovic said about Murray. "I must say, it was a little bit of a strange experience to have him at courtside in my box. We played for over 20 years against each other at the highest level. Great to have him on the same side of the net. He gave me some great advice mid-match."

Before heading out into Rod Laver Arena, Djokovic and Murray chatted in the gym. They wrapped up the conversation with a fist bump, before Djokovic hopped on the treadmill to warm up.

During the match, apart from an extended conversation before the fourth set, there was only the occasional interaction between player and coach - a pairing between 37-year-olds born a week apart, and opponents from the age of 12, including in a series of Slam finals as pros. Murray retired at the Paris Olympics in August; Djokovic proposed teaming up in November.

As a player, Murray was known for mid-match dramatics, plenty of gesticulating and muttering, often directed at his entourage. Djokovic does similar.

Djokovic showed some of his usual fire when that vital break came at the 1 1/2-hour mark. He watched the 107th-ranked Basavareddy's forehand land wide and let out a yell, clenched a fist, pointed a finger at his ear. That was the beginning of the end for Basavareddy, who started stepping gingerly between points and grabbing at his legs, and took a medical timeout before the third set.

On a busy and warm Day 2, which included nine Grand Slam champions with a combined 43 major trophies in action plus another half-dozen players with runner-up showings, the winners included No. 2 Iga Swiatek, No. 3 Coco Gauff and No. 7 Jessica Pegula among the women, and No. 1 Jannik Sinner and No. 3 Carlos Alcaraz among the men.

Naomi Osaka, who won two of her four major titles in Australia, faced Caroline Garcia in Monday's last match at Rod Laver Arena.

Noteworthy exits came from two-time Australian Open champion Victoria Azarenka, 2017 French Open champion Jelena Ostapenko, and two-time major finalist Stefanos Tsitsipas. Ostapenko's 6-3, 7-6 (6) loss came against Tokyo Olympics gold medalist Belinda Bencic, who is ranked outside the top 400 after returning in October from maternity leave.

Also one-and-done, but not that surprisingly: Nick Kyrgios, who lost to Djokovic in the 2022 Wimbledon final and played one match the past two seasons because of injuries. Kyrgios dealt with a strained abdominal muscle in the lead-up to this week and was defeated by Jacob Fearnley 7-6 (3), 6-3, 7-6 (2).

"Sorry for Nick," said Fearnley, a 23-year-old from Scotland who played college tennis at TCU in Fort Worth, Texas. "I could tell he was dealing with some stuff."

The intensity and physicality of the points against Djokovic wore on Basavareddy. Another key: Djokovic's backhand grew faster in the second set, while Basavareddy's shots off that wing slowed. And one more: Djokovic hit 23 aces.

At 3-all, a half-hour in, Basavareddy moved out front by breaking Djokovic with a backhand return winner. Soon enough, that set belonged to the youngster, who is not shy about saying the Serb is his favorite player. Basavareddy showed off some great touch with drop shots and lob winners, while hanging in there at the baseline with the consummate baseliner.

"Very complete player," Djokovic said. "He did very pleasantly surprise me with all of his shots and his fighting spirit toward the end."

They are currently separated by exactly 100 spots in the ATP rankings. The gulf is far wider, of course, when it comes to experience and accomplishments.

This outcome left Basavareddy's career record at Grand Slam tournaments at 0-1; his tour-level debut only came in December. Djokovic, meanwhile, picked up his record-extending 378th victory at a major on Monday; he hasn't lost in the first round of one since bowing out at that stage of his first two Australian Opens in 2005 and 2006.

"He didn't get carried away by the significance of the moment," Djokovic said about Basavareddy. "I'm sure we'll see a lot of him in the future."

After wasting a set point in the second tiebreaker with an ill-conceived drop shot, Jannik Sinner quickly reverted to what's been working for him and finished off a straight-set win over Nicolas Jarry to begin his Australian Open title defense.

The 7-6 (2), 7-6 (5), 6-1 victory on Rod Laver Arena extended Sinner's winning streaks to 15 on both the tour and on hard courts in Grand Slams.

After all the pre-tournament attention on the 2024 doping cases of Sinner and long-time women's No. 1 Iga Swiatek, both started the year's first Grand Slam tournament about the same time on nearby courts on Day 2.

"Yeah, I was curious to see how it was," Sinner said of the reception at Rod Laver, where he became a fan favorite last year. "You never know what's happening. I was happy about the crowd. It was a nice atmosphere."

Top-ranked Sinner had to grind for two long, tiebreak sets against No. 35-ranked Jarry, a 29-year-old from Chile, before finding his touch.

"It was a very close one because the first sets, they can go both ways," Sinner said. "In the third set when I broke it the first time, that gave me a little bit of room to breathe.

"I'm happy how I handled the very tough situation."

Sinner has got a good record at Melbourne Park in that department. He rallied from two sets down in last year's final to beat Daniil Medvedev for his first Grand Slam title, coming off a semifinal upset of 10-time champion Novak Djokovic.

While Sinner was deep into his match against Jarry, Swiatek, a five-time major winner from Poland, fended off top-ranked doubles player Katerina Siniakova 6-3, 6-4 on John Cain Arena.

Coco Gauff had a little difficulty adjusting to the sun at one end of Rod Laver Arena in Monday's first marquee match and dropped an early service game before quickly settling into a rhythm in a 6-3, 6-3 win over 2020 champion Sofia Kenin.

Third-seeded Gauff beat Swiatek to win the title at the WTA Finals last November and started this season by helping the U.S. to victory at the United Cup last week, against beating No. 2 Swiatek in the final.

Gauff, the 2023 U.S. Open champion is wearing a Marvel-inspired bodysuit and skirt at Melbourne Park and she's radiating confidence and calm.

"I knew going in it was going to be difficult, but you know I'm happy with how I played," she said of the 1-hour, 20-minute win over Kenin, who at No. 81 is a much tougher opponent than her ranking suggests.

"I mean (I) could serve better, but like on that side I was struggling to see the ball," Guaff said, pointing to one baseline on the main show court that was bathed in sun. "So I'm just happy that I was able to manage through that."

Another 20-year-old American, Alex Michelsen, produced the biggest win of his young career with a 7-5, 6-3, 2-6, 6-4 first-round upset of 2023 Australian runner-up Stefanos Tsitsipas.

Michelsen's three booming service returns in the ninth game of the fourth set helped him earn a vital break against the 11th-seeded Tsitsipas and, after shaking off jitters on his own serve, he closed out for his first victory over a player ranked in the top 20 at a Grand Slam. No. 17 Frances Tiafoe advanced in five sets over Arthur Rinderknech of France.

Gauff went into her opening round on a streak of winning 33 matches against players ranked outside the Top 50, dating to a loss to Kenin at Wimbledon 2023.

The draw presented another tough trip to Australia for Kenin. It was the third straight year Kenin faced a Grand Slam champion in the first round in Australia, and her fourth consecutive first-round exit here.

Gauff will next play Jodie Burrage of Britain. No. 7 Jessica Pegula also advanced along with No. 12 Diana Shnaider, No. 28 Elina Svitolina, and Belinda Bencic, who ousted No. 16 Jelena Ostapenko. Lucia Bronzetti of Italy advanced over No. 21 Victoria Azarenka, a two-time Australian Open champion.