Petra Kvitova withdrew from the French Open on Monday due to an injury to her forearm, hours before her first match at the tournament against Romania`s Sorana Cirstea.
"I`m so disappointed to have to announce my withdrawal from Roland Garros," the sixth seed said on Twitter.
"I`ve had pain in my left forearm for a few weeks and last night an MRI confirmed a grade two tear which could unfortunately could get a lot worse if I play today."
The Czech player has been replaced in the draw by lucky loser Kaja Juvan of Slovenia.
Kvitova, a semi-finalist in Paris in 2012, made a strong start to the clay court season by winning the title in Stuttgart and reaching the quarter-finals in Madrid.
A left calf injury in the third round at Rome affected her momentum heading into Roland Garros, the venue of her return to tennis in 2017 following a knife attack.
"Two years ago, I made my comeback here at Roland Garros, so I`m truly sad not to be able to play here this year. It`s a really tough decision to make," she added.