Swiatek breezed through the opening set against the unseeded Cristian in just 35 minutes, breaking at the first opportunity and repeating that feat in the eighth game to take the lead.

But world number 60 Cristian dug her heels in and proved much tougher to crack during the second set on Court Suzanne Lenglen.

Poland’s Swiatek successfully defended six break points, having not faced a single one in the first set, before breaking at 6-5 to wrap up victory in one hour and 56 minutes.

Swiatek will face Kazakhstan’s 12th seed Elena Rybakina or Latvian 21st seed Jelena Ostapenko in the fourth round.

“It was 20 degrees when I played my first match but today it was 30 degrees. It is not easy to adjust but I have played in every condition,” said Swiatek.

“Last year at the Olympics it was super hot so I was ready for it. You need to change in different conditions, adjusting the equipment is the best way. I went one kilo up on both strings.”

The 23-year-old, who won bronze at the 2024 Paris Olympics, is known as the ‘Queen of Clay’ after winning four of the past five French Open titles.

Swiatek comfortably dispatched Britain’s Emma Raducanu in the second round but has endured a mixed clay-court swing – reaching the semi-finals of the Madrid Open but suffering early exits in Stuttgart and Rome – and has been facing questions about her form.

Elsewhere, Italian fourth seed Jasmine Paolini eased past Ukraine’s Yuliia Starodubtseva in a 6-4 6-1 victory.

Paolini, who reached the final at Roland Garros 12 months ago, could face another Ukrainian, Elena Svitolina, or American Bernarda Pera in the fourth round.

China’s Zheng Qinwen also continued her charge through the field with a third successive straight-set victory.

The eighth seed beat 18-year-old Grand Slam debutant Victoria Mboko of Canada 6-3 6-4 and will face Russian Liudmila Samsonova for a place in the quarter-finals.