Ana Ivanovic made a winning start to her US Open on Day 2, beating Elina Svitolina, 63 62.
Sofia Arvidsson did as well, beating Japanese veteran Kimiko Date-Krumm in straights, 64 62.
Kimiko Date-Krumm is a two-time quarterfinalist at the US Open, but back in 1993 and 1994.
Elena Vesnina pulled off one of the first upsets of the day, beating No.32 seed Peng Shuai.
Bethanie Mattek-Sands sported blue hair on court - and she got off to a 2-0 start, too.
But Venus Williams came roaring back, winning 12 of the next 14 games to move through, 63 61.
Dominika Cibulkova, a 2010 quarterfinalist here, rallied to beat Johanna Larsson, 67(5) 62 60.
Sloane Stephens pulled off an upset over No.22 seed Francesca Schiavone later on, 63 64.
Francesca Schiavone was playing her 49th straight Slam - the record among active players.
No.8 seed Caroline Wozniacki was also sent home on Day 2, losing to Irina-Camelia Begu, 62 62.
Serena Williams didn't let the upset bug bite her though, beating Coco Vandeweghe, 61 61.
Serena Williams has won 37 of her last 39 matches and next faces Maria Jose Martinez Sanchez.