Williams posted an update on her Instagram account Tuesday, calling the ailment "incredibly frustrating." The 23-time Grand Slam champion was waiting for an MRI.
"So today has been interesting already," Williams said in an update on her Instagram Story. "I just finished one exam with my doctor. The news was actually super exciting so I'm really happy about that. I'm having an MRI soon, but I wanted to keep you guys totally updated while I wait ...
"Thanks for the support and the love and the understanding. It has been incredibly frustrating but also I'm excited because I feel like I've been playing really well and I can only go up. I'm looking so forward to going up. Hopefully you guys will be there to continue to cheer me on."
The French Open marked Williams' return to the Grand Slam circuit. She won her first match back on the big stage and was cruising into a fourth-round match with Maria Sharapova, before she withdrew from the tournament at Roland Garros.
While Williams has not provided an update about the MRI results, Dr. Armin Tehrany, founder of Manhattan Orthopedic Care and NYPD Honorary Surgeon, said that Williams is most likely dealing with a pectoralis strain.
Tehrany has worked with the team physicians for the New York Jets, New York Rangers, New York Islanders and with professional tennis players.
"The type of rehab for this would call for rest, massage, electrical stimulation, and a combination of ice and heat," the surgeon told UPI Tuesday.
Tehrany said the risks of coming back too early will depend on the results of the MRI.
He also said that it is possible that she could be ready and 100 percent healthy for Wimbledon.
The first round of the grass court Grand Slam is set for July 2 in London. Williams is a seven-time Wimbledon singles champion.
She is slotted at No. 451 in the latest Women's Tennis Association world rankings.