Dayana Yastremska replaces two-time AO champion Osaka in the draw.
The 42-year-old Williams withdrew with an unspecified injury.
The former World No.1 wants to finish on her own terms.
Dick Savitt was the first Jewish player to win Wimbledon, the Australian and appear on Time Magazine cover.
Mardy Fish's tenure as U.S. Davis Cup captain is done.
The World No.1 suffered her worst loss in some time, but her confidence remains in place.
The British star hurt herself during her round of 16 encounter at the ASB Classic.