MELBOURNE, Australia -- The bugs bothered Carlos Alcaraz in his first match at the Australian Open in two years, and so did 37-year-old veteran Richard Gasquet.

For the first set, at least.

After taking an hour and 12 minutes to clinch the opener in a tiebreaker, No. 2-ranked Alcaraz raced through the rest of the match in another hour against the tiring, sweat-soaked Frenchman for a 7-6 (5), 6-1, 6-2 win Tuesday night.

The first two games took a combined 17 minutes, with the 20-year-old Alcaraz needing a few moments to try to remove a persistent insect that was bothering him behind the baseline just before he held for 1-1.

Both players used their rackets to push the bugs away from the court after the eighth game, and Alcaraz was at it again after the first set.

There were few distractions after that until Alcaraz was serving for the match and the game went to deuce five times before he closed with an ace.

He threw in some drop shots and slices that made Gasquet run, saying it shows he's "playing for myself, but I always try to make the people enjoy watching tennis."

"Every set, I played better and better," he said. "In the end, I played at quite a good level."

He will next play Lorenzo Sonego, who beat Dan Evans 4-6, 7-6 (8), 6-2, 7-6 (4).

Sixth-seeded Alexander Zverev dropped the first set before rallying to beat fellow German Dominik Koepfer 4-6, 6-3, 7-6 (3), 6-3 in a night match on Margaret Court Arena.

The win came a day after Zverev, 26, was ordered to stand trial later this year in an assault case in Germany, though the men's tennis tour ruled last January that Zverev would not face disciplinary action after its own investigation.

Zverev was a finalist at the US Open in 2020, won the men's singles Olympic gold medal in 2021 and is sixth in the rankings.

He led Germany to victory in the United Cup team tournament in Sydney last week, but said playing a Grand Slam tournament in Melbourne was very different.

Zverev said he was seriously tested by Koepfer and was struggling for rhythm, but added: "You've got to focus on yourself, your own shots."

Amid blazing heat and blustery conditions earlier Tuesday, at least one player was enjoying the weather, as Norwegian Casper Ruud basked in the sunshine during a routine 6-1, 6-3, 6-1 win over Albert Ramos-Vinolas.

"It's minus-20 [Celsius] back home, so it's quite a change. It's much nicer to be in the warm summer weather," said the 11th-seeded Ruud, who lost in the second round in 2023.

"The body and tennis is feeling great," Ruud said. "Hopefully I can have a good run down here. It's been a couple years in a row where I wasn't able to play as well as I hoped here. Hopefully 2024 we can turn that around."

In other men's results, Denmark's Holger Rune needed four sets and more than 3 hours to get the job done against Japan's Yoshihito Nishioka as the No. 8 seed wrapped up a 6-2, 4-6, 7-6 (3), 6-4 victory.

Britain's Jack Draper struggled in the heat and had his blood pressure checked midway through his 6-4, 3-6, 4-6, 6-0, 6-2 win over Marcos Giron, while compatriot and 19th seed Cameron Norrie defeated Juan Pablo Varillas 6-4, 6-4, 6-2.

No. 32 seed Jiri Lehecka, fresh off winning his first title at the Adelaide International, continued his strong form Down Under; a quarterfinalist last year, he cruised to a 6-3, 6-2, 6-3 victory over Spain's Bernabe Zapata Miralles.

No. 23 seed Grigor Dimitrov, another early 2024 title winner following his Brisbane success, rallied from a set down to defeat Marton Fucsovics 4-6, 6-3, 7-6 (1), 6-2.

Indian qualifier Sumit Nagal earned his second Grand Slam main draw win with an upset of 31st-seeded Alexander Bublik, winning 6-4, 6-2, 7-6 (5).

Last year, Alcaraz had to withdraw from the Australian Open because of an injured right leg. That was the rare hiccup in a run of four major tournaments that netted him two titles -- the 2022 US Open and Wimbledon last year -- and trips to the semifinals.

Gasquet was playing in his 17th Australian Open and his 73rd Grand Slam singles draw overall -- tied for third with Novak Djokovic in the Open era.

A first-round loss in Auckland last week ended Gasquet's streak of 843 consecutive weeks in the top 100 dating back to April 2005.

The Associated Press and Reuters contributed to this report.