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 him a "thief."
    After the match, while Osaka accepted the trophy, boos rang around Arthur Ashe Stadium. Osaka wept.
      "Not only was a game taken from me but a defining, triumphant moment was taken from another player, something she should remember as one of the happiest memories in her long and successful career," the 37-year-old Williams wrote. "My heart broke."
      As the days passed, Williams said in the essay, she started seeing a therapist and wasn't ready to pick up a tennis racket. She decided to write to Osaka, and here is what she said: