Serena Williams has sailed into the third round of the Australian Open after weathering an early challenge from Russian Vera Zvonareva.
The former world number two broke Williams twice in the first set but the top seed broke back and took the first set 7-5.
Williams went on to dominate, taking the second set 6-0.
Her sister Venus Williams beat fellow American Lauren Davis in two sets and said she was grateful just to be playing.
"Appreciative for good health because, you know, there was a period where I couldn't even play professional tennis," she says.
"Able to feel good every day because, you know, there was a point where I didn't. To overcome that, I'm grateful."
Sixth seed Agnieszka Radwanska has also advanced to the third round.
In the men's draw Novak Djokovic's Australian Open tennis campaign shifted up a gear with a 6-0 6-1 6-4 thrashing of Russian Andrey Kuznetsov to move into the third round.
The defending champion Stan Wawrinka also advanced after beating the Romanian qualifier Marius Copil 7-6 7-6 6-3.