Iga Swiatek continues her bid to become the first woman in 16 years to win back-to-back French Opens on Thursday as Alexander Zverev returns to the court where 12 months ago his dreams of a maiden Grand Slam crown ended in agony.

World number one Swiatek celebrated her 22nd birthday on Wednesday and is expected to comfortably ease past Claire Liu of the United States to make the last 32.

Liu, ranked 102 in the world, managed to win just one game when she faced the Pole at Indian Wells this year.

Victory in Paris this year would give Swiatek a fourth Grand Slam title, taking her alongside Naomi Osaka, Kim Clijsters and Arantxa Sanchez-Vicario and one behind Maria Sharapova and Martina Hingis.

However, Swiatek insists she is not motivated by landmarks.

"I don't even know these records. I play tennis but I'm not really an expert in terms of statistics and history, so I'm not really focused on that," she said.

"I'm kind of living in a different world. I never even played Serena or Monica Seles. So I'm kind of living my own life and having my own journey."

Justine Henin, a seven-time major winner, was the last woman to successfully defend the title at Roland Garros back in 2007, her third in a row and fourth in total in Paris.

Zverev was on a journey to a potential place in the final last year, matching Rafael Nadal blow for blow in a bruising semi-final until the German collapsed to the ground with ankle ligament damage.

He was taken off court in a wheelchair and never played again in 2022.

On Thursday night, he returns to the same Court Philippe Chatrier where his dreams were dashed to face Slovakia's Alex Molcan, the world number 86.

Zverev, who was the third seed last year, is only seeded 22nd this time around, but the Olympic champion had enough to beat South African Lloyd Harris in straight sets in the first round on Tuesday.

"It's nice to be back. I've marked this day in bold on my calendar since last year," said Zverev who was also a semi-finalist in 2021.

Zverev and Molcan weren't initially to play the night match on Chatrier but they were summoned as late replacements when Gael Monfils withdrew from his match against Holger Rune due to a wrist injury.

The bottom half of the men's draw has opened up after world number two Daniil Medvedev was knocked out in the first round by Brazil's Thiago Seyboth Wild.

Fourth seed Casper Ruud and runner-up to Nadal last year, who was Medvedev's scheduled semi-final opponent, takes on Italian qualifier Giulio Zeppieri, ranked 129.

Wimbledon champion and women's fourth seed Elena Rybakina, who could take Swiatek's world number one ranking at Roland Garros, faces a Czech teenager for the second time.

Having defeated Brenda Fruhvirtova, Rome champion Rybakina will face Linda Noskova.

Victory on Thursday would give Rybakina a 30th win of 2023.

Coco Gauff, the runner-up to Swiatek last year, faces Julia Grabher of Austria who is making her Roland Garros debut this year.