When Serena Williams withdrew on Monday from the French Open, less than an hour before her highly anticipated fourth-round match against Maria Sharapova, she admitted it was because of a pectoral injury that had struck her for the first time two days earlier.

The sense of deflation and surprise around Roland Garros was palpable, from the locker room to the media desks to the paid seats on Court Philippe-Chatrier, where anticipation of a 22nd showdown between the two fiercest rivals in tennis had risen like the mercury on another sultry afternoon.

Sharapova gets a walkover into the quarter-finals and, technically, a “W” to go with only two wins against 19 defeats in 14 years, not the most satisfying of replies. It would take Machiavelli to construct a theory that the American had laid one last glove on the Russian with her broadside about Sharapova’s book being filled with “hearsay” before withdrawing from a match she already knew she could not win.

Sign up to The Recap, our weekly email of editors’ picks.

Sharapova issued a response that sounded like something from the central office of information: “I was looking forward to my match against Serena today and am disappointed that she had to withdraw. I wish her a speedy recovery and hope she returns to the tour soon.”

Williams, as if by duty, echoed the sentiment: “It’s very difficult, because I love playing Maria. It’s a match I always get up for.”

Kim Clijsters, who won two major titles after having her first child at 25, made a sharp observation. “I was interested to hear she had never had this injury before. New aches and pains come along after you’ve had a baby. It took me a good nine to 10 months to come back. I was a little surprised she played doubles.”

Williams was returning to a major for the first time since winning the 2017 Australian Open and she could not say if she would be fit for Wimbledon, although the tone of her reply did not give cause for optimism. “I’m going to get an MRI tomorrow,” she said. “I’m going to stay here and see as many specialists as I can. And I won’t know that until I get those results.”

Adam Zagoria (@AdamZagoria) Video shows Serena couldn’t even carry her bag off court Sunday b/c of her pec injury. pic.twitter.com/iglWZlnWOa

In her previous press conference, after she defeated Julia Görges in an hour and a quarter on Saturday, Williams made no mention of the injury. She said she would have to leave quickly and, asked if anything was wrong, she replied: “No, I need to get back to my baby. She’s still awake. I need to go home.”

On Monday, however, she said: “The first time I felt [the injury] was against Görges in my last match. That’s when I started to feel it. It was really painful and I didn’t know what it was. It didn’t start before I got here.”

When she and her sister Venus went out in three sets in the third round of the doubles on Sunday Serena’s normally intimidating serve was down to 73mph, nearly 50mph below her potential quickest.

“In my doubles I tried a lot of different tapings, lots of different types of support to see how it would feel under match circumstance. It didn’t get a lot better. I have been having some issues with my pec muscle and it has unfortunately been getting worse, to the point where right now I can’t actually serve.

Rafael Nadal seals 900th win by beating Maximilian Marterer Read more

“I have made every sacrifice that I could. I made a promise to myself, my coach and my team that, if I’m not at least 60% or 50%, then I probably shouldn’t play. The fact that I physically can’t serve at all is a good indication that maybe I should just go back to the drawing board and stay positive and try to get better and not get it to a point where it could be a lot worse.”

Nevertheless, pulling out so late from the match everyone had been waiting for was probably not the public relations coup of the season. It is not so much that she changed her story as provided a version that challenged the timing of the facts.

As for the nature of the injury, she said: “There are a lot of theories. I have never felt this in my life. This is so painful. I don’t really know how to manage it yet. When you do have an injury that you have had before, you can kind of manage it, and I have pretty much had every injury in the book. But this is a little different. I’m clueless as to what to do. I’m just going to do what the doctor thinks I should do and get all the evaluations on it.” Her coach, Patrick Mouratoglou, told the Tennis Channel, “We’ll know tomorrow whether we need two weeks, three weeks – I hope not more – for her to be able to serve again.”

For all the agonising and controversy the bottom line is Williams has been playing professional tennis since 1995. She turns 37 before her daughter’s first birthday.

In the quarter-finals Sharapova faces Garbiñe Muguruza, champion here in 2016, who played only two games more before her opponent, Lesia Tsurenko, retired with a thigh injury.