LONDON -- Venus Williams does not remember her first professional main-draw match on grass.
Told that, like her first-round match Monday at Wimbledon, it also was a double bagel, Williams' eyes grew wide.
"Did I lose?" she asked.
No, she was informed. Like her 6-0, 6-0 victory against 36th-ranked Madison Brengle on Monday, Williams also won that long-ago match. And there was another notable similarity.
In '97, after winning three qualifying matches at Eastbourne, Williams defeated another American, Chanda Rubin.
"I'm sure I enjoyed it," cracked the five-time Wimbledon champ.
No doubt she enjoyed the ease of her victory over Brengle in their first meeting as well, one of 11 matches Monday involving 12 American women.
"I don't think she played badly," Williams said. "I was just able to convert on the important points."
Williams has had only one other double bagel at a Grand Slam, over Mirjana Lucic-Baroni at the 2002 US Open in another first-round match.
Williams could meet sister and Wimbledon doubles partner Serena -- a 6-4, 6-1 winner over Margarita Gasparyan Monday -- in the fourth round. If it happens, it would be the first time the sisters have met in a Grand Slam since the final of Wimbledon in 2009, and the earliest they have met in a major since the fourth round of the 2005 US Open.
"It would be great if I can continue to play well and get there," Venus said.
Among the other Americans in action Monday, Bethanie Mattek-Sands, Sloane Stephens, Coco Vandeweghe and Lauren Davis advanced, while Alison Riske, Irina Falconi, Shelby Rogers, Edina Gallovits-Hall and Nicole Gibbs lost their first-round matches.
Riske's 3-6, 7-5, 6-3 loss to Lucie Safarova was a particular disappointment because she was up 6-3, 4-2 against the French Open finalist and sixth seed. The match featured 11 service breaks combined.
For the 44th-ranked Riske, who lost in straight sets to Safarova in Madrid in May, the third-round exit comes after two straight third-round appearances here.