Top seed Coco Gauff cruised into the second round of the Auckland Classic on Tuesday while two former Grand Slam winners featured in rain-disrupted encounters.

The 18-year-old American, ranked seventh in the world, downed 35-year-old German veteran Tatjana Maria 6-4, 6-1 in a match that only lasted 82 minutes even with multiple stoppages as brief showers swept over the city.

Gauff, who has been as high as world number four, has only two minor titles to her credit and will be looking to win major trophies in 2023 but her game was marred by inconsistency on Tuesday.

After a powerful start that saw her race to a 4-0 lead in the first set, Gauff was broken twice by Maria who fought back to level at 4-4.

But Gauff composed herself to win eight of the next nine games and wrap up the match.

Emma Raducanu, the 2021 US Open winner, rallied from a set down to outlast rising Czech star Linda Fruhvirtova 4-6, 6-4, 6-2 with two rain breaks stretching the match to nearly four hours.

In her first competitive outing since being sidelined last October by a wrist injury, the 20-year-old Briton showed signs of rust as she lost the first set to Fruhvirtova, three years her junior, and was down 0-2 in the second before her fortunes changed.

"I was like, you need to stop this and just pick it up, like be more aggressive and swing more freely," said Raducanu as she explained moving up several gears to win four straight games to take control of the second set and then break twice more at the start of the decider.

"It's always difficult playing your first match of the year, so it was always going to be a little bit of a challenge, especially with the conditions," she said.

"I was loving the support. I felt like everyone was behind me and I absolutely loved it. Some moments it was tricky in the score and I would hear a young kid say 'Come on Emma' and I was like, 'come on, let's go'."

The match between number two seed Sloane Stephens, the 2017 US Open champion, and Spain's Rebeka Masarova was halted to be completed Wednesday with Masarova up 2-1, 30-0 in the first set.

The first-round match for 2020 Australia Open champion Sofia Kenin against Xinyu Wang was also put back to Wednesday.