Serena Williams has never served faster.
And she's doing it by not trying to hit the cover off the ball.
Williams had one serve clocked at 207km/h in her 6-1 6-3 third-round victory over Japan's Ayumi Morita at the Australian Open on Saturday.
It equalled her fastest-ever delivery which came two days ago in the previous round at Melbourne Park.
The No.3 seed began the first grand slam tournament of the year as the short-priced favourite, a status confirmed after she dropped just six games in her opening three matches.
Williams' serve is just one of many aspects of her game she is happy with.
"I went for it, but I wasn't going for it that hard," she said.
"Every time I go for it, to hit it really hard, it goes in the 190s.
"When I hit the 207, I was like 'OK, the first one wasn't luck, maybe I can hit a 207'.
"So it was pretty cool."
And she won't be deliberately trying to go even faster in her fourth-round clash with Russian No.14 seed Maria Kirilenko.
"My job is to do the best I can," said Williams, who won the most recent of her five Australian Open titles in 2010.
"Maria is playing consistent tennis, especially the past 16, 18 months, she's been so consistent.
"So my goal is just to be really focused against a player that's doing so well."
Williams is also happy that the ankle problem she picked up early in the tournament is improving slowly day by day.