Rome, Italy (SportsNetwork.com) - Serena Williams and Andy Murray each withdrew from this week's French Open tune-up in Rome on Thursday.

Williams cited an elbow injury that began during the previous tournament in Madrid, while Murray said he was fatigued after winning each of the last two events in Munich and Madrid.

"It's been a very long three weeks for me, the longest I've ever had on clay," said Murray, who had never even reached a clay-court final before his triumph in Munich.

Murray followed that with a surprising win in Madrid, beating Rafael Nadal in the final.

"The point is I did not expect to do what I have done in the past few weeks," Murray added. "My body has never done that before on clay. My body's always found the surface difficult. I also don't want to risk making it worse. In the past maybe I've done too much."

The French Open is just over a week away, as the year's second Grand Slam starts May 24 in Paris. Murray's best results at Roland Garros were semifinal appearances in 2011 and last year.

"I wanted to play in this tournament, it's a big event with a lot of points on offer," Murray continued. "The time of year is tough for everyone, it's just one of those things."

David Goffin of Belgium earned a spot in the men's quarterfinals with the walkover win against Murray.

Williams, meanwhile, was scheduled to face fellow American Christina McHale in the women's third round on Thursday.

"It was not an easy decision, I talked to my coach who said it would not be a smart thing to play," said Williams. "I hate quitting. But this is not quitting, it's just making a better decision."

Williams was the two-time defending Rome champion and also won the title in 2002.

"I love playing in Rome and have a lot of friends here," Williams added. "Pulling out is not fun but everyone is adult and understands the importance of someone doing the best they can at this stage of their career. It is nothing personal."

Williams, who was the top seed in Rome, will be the top seed in Paris just 10 days from Thursday. She lost in the second round last year at Roland Garros after capturing her second French Open title in 2013.