Serena Williams has admitted that she always suffers from "first-round jitters" after beating Alison van Uytvanck in straight sets earlier.

The world number one looked to be cruising after wrapping up the first set 6-0, but had to battle to edge out the Belgian in the second.

The five-time Australian Open champion told reporters: "It is never easy, I always have first-round jitters and I do get nervous. It is good to come out with a win and I felt really good out there.

"I thought [Van Uytvanck] played really well and especially in the second set. The first set she was just kind of finding her mark and then in the second set we saw why she is so good. I was happy to get through that."

Williams will play Russia's Vera Zvonareva in round two.