MELBOURNE, Australia -- Back on Tuesday, when 20 Americans were still alive in singles, this Australian Open seemed full of possibilities.
As of Friday, there were five Americans left in the draw, and when the second week dawns on Sunday, a solitary U.S. player will be left in the top half of the men's and women's draws: the ageless Venus Williams.
Technically, she's 36 years old, but the fact that she remains a usual suspect at the back end of Grand Slams is a tribute to the zest she continues to bring to the game.
On Friday, Williams played her best match so far, wrecking Duan Ying-Ying, 6-1, 6-0 in a third-round match that was devoid of drama.
It was over in 59 minutes, and Williams won 61 of 96 points. Duan was no random qualifier or an overmatched wild card but rather China's fifth-ranked player riding her best Grand Slam result ever.
"I was lucky to have more experience today," Williams said afterward. "I'm happy to be in fourth round against a player who is playing really, really well."
This was Williams' easiest win at the Australian Open in four years; she beat Galina Voskoboeva in the first round in 2013 by the same score.
Williams, the No. 13 seed, next plays Mona Barthel, a match that could vault her into her ninth Australian Open quarterfinal.
Asked how it felt to reach her 10th fourth round here, Venus smiled.
"Oh, yay!" she said. "It's good. It's never enough. I've been in the fourth round before. I've tasted it before, and it's always a great feeling because it means, hey, I have an opportunity for the quarterfinals.
"That's what I'm going to go for."
Williams has improved her precision in each of her matches, lowering her total of unforced errors from four to 24 to 18 against Duan.