Having played through the pain in recent weeks, the sixth seed and Australian Open finalist has withdrawn from the French Open.
Petra Kvitova has withdrawn from the French Open ahead of her opening match on Monday due to an arm injury.
Two-time grand slam champion Kvitova had been due to face Sorana Cirstea in the first round, but she announced her "really tough decision" just hours before she was due on Court Suzanne Lenglen.
The world number six retired from her last-16 match at the Internazionali d'Italia earlier this month and revealed on Monday she had been playing through pain in recent weeks.
A scan on Sunday confirmed the Czech star would need to skip Roland Garros.
Kvitova: "It is a really tough decision to make"
Sorry to have to inform you of some bad news this morning pic.twitter.com/snxhJkPRuh— Petra Kvitova (@Petra_Kvitova) May 27, 2019
Kvitova post on Twitter: "I'm so disappointed to have to announce my withdrawal from Roland Garros.
"I've had pain in my left forearm for a few weeks and, last night, an MRI confirmed a grade two tear, which unfortunately could get a lot worse if I play today.
"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 is a really tough decision to make, but I wish the tournament all the best for a successful event and can't wait to be back in 2020."
Kvitova's best performance at the French Open saw her reach the semi-finals in 2012, where she lost to eventual champion Maria Sharapova.
The 29-year-old was the victim of a career-threatening knife attack in late 2016 but returned to the court and reached the Australian Open final - her first in a major since the incident - earlier this year.