Two of the four scheduled matches didn't even take the court due to walkovers, with No.7 seed Sabine Lisicki pulling out before her match against Stefanie Voegele due to gastrointestinal illness, and then Australian qualifier Ashleigh Barty giving a walkover to No.3 seed Sharapova due to an adductor tear.
"Obviously it's really disappointing that I can't go out there and play my match against Maria, and also have the opportunity to play the doubles with Casey again," Barty said. "It's a tough decision but a smart one that we have to make. Unfortunately I won't be able to play in Hobart next week either.
"I need to give my body 10 to 12 days to recover and hopefully be right for the Australian Open."
Another one of the matches took the court but didn't finish - No.5 seed Kerber was leading Anastasia Pavlyuchenkova, 62 43, when the Russian, a finalist here last year, had to stop due to a thigh injury.
"I saw that Anastasia had something on her leg and couldn't run at the end," Kerber said. "It's not easy to play against someone like that because you know the other one can't run, but you need to try just focusing on your game as though she is still fit. You need to do that and just focus on yourself."
Kerber was asked why she thought there have been so many withdrawals in Week 1 of the season.
"You have like six weeks off and you are practicing, but the matches are so much different than the practice things," the German said. "So maybe that's why we are having so many withdrawals right now. When you play against somebody in practice it's much different than playing real matches."
"It's great to just finally be out there," Azarenka said. "It was a long wait. I couldn't wait to go out there. It was good to be there in front of the crowd and play competitive - that's really what I love to do.
"I was still getting into it towards the end of the second set. I think towards the end it's important to just be the same way as you started the match and to keep that pressure, because in the end anybody can come back. They're loose. They have nothing to lose. And actually that's what kind of happened in the last game - Casey went for some amazing shots and that's it. I'm glad I wrapped it up in that game."