Serena Williams has withdrawn from this month's Italian Open. Her announcement comes five days after she opted out of the WTA event in Madrid.
Williams is a four-time winner of the competition and is also a doubt for the French Open which starts on May 27, 2018.
The 23-time Grand Slam champion has not played a match on clay since reaching the final at Roland Garros in 2016. She returned to the WTA Tour in March and reached the third round at Indian Wells, where she was beaten by sister Venus, before falling in the first round of the Miami Open to Japan's Naomi Osaka.
Williams' ranking has also dropped from 1 to 454.