Serena Williams said she owed Naomi Osaka an apology after the US Open. Osaka's response brought her to tears

    Serena Williams defeated Alison Riske to advance to the semifinals at Wimbledon on Tuesday.

    (CNN)Something was keeping Serena Williams from moving forward after her loss to Naomi Osaka in last year's US Open final. She believed she owed Osaka an apology, Williams revealed in an essay published Tuesday in Harper's BAZAAR.

    While a then-20-year-old Osaka prevailed against her idol 6-2, 6-4 in New York to win her first major, it was overshadowed by controversy, with Williams clashing with chair umpire Carlos Ramos, culminating when he docked her a game for calling