PARIS — After Serena Williams won her 23rd Grand Slam singles title three months ago at the Australian Open, her coach, Patrick Mouratoglou, was surrounded by reporters in a corridor at Melbourne Park.
Full of optimism for the 2017 season after Williams’s commanding march to the title, he did not rule out the possibility of another run at the true Grand Slam — winning all four major tournaments in a calendar year.
Mouratoglou had no idea then that Williams was pregnant.
“I don’t know who knew, but I didn’t know, that’s for sure,” he said Friday in a telephone interview from Nice, France.