The 41-year-old Venus, who has seven Grand Slam titles to her name, said she would miss competing at her "favorite slam" and wished all the other players good luck
Kenin made 18 unforced errors in an unconvincing first-set display but broke decisively in the 11th game with her sixth consecutive point as she bagged seven games in a row to open up a 4-0 lead in the second.
Australian Open organisers announced Friday that players would compete in a biosecure "bubble" after the host city was ordered into a snap five-day lockdown, with spectators banned.
Osaka then lifted her intensity, opening to a 4-0 lead before Boulter unexpectedly peeled off three straight games. But the Japanese star refocused to force a deciding set, which she ran away with.
Kenin won her maiden Grand Slam in Melbourne last year which set the American on course to break into the top 10 and claim the WTA Player of the Year award.
I definitely think I can talk to Novak... I think that will be helpful since we're both defending champions.