|US Open 2019|
|Venue: Flushing Meadows, New York Dates: 26 Aug – 8 Sep|
|Coverage: Live text and radio commentary on selected matches on the BBC Sport website and app|
Former Wimbledon champion Garbine Muguruza was knocked out of the US Open in the first round with a 2-6 6-1 6-3 defeat by Alison Riske.
American Riske, ranked 11 places below the Spaniard at 36th, sealed her first win at Flushing Meadows since 2013.
Two-time Wimbledon champion and sixth seed Petra Kvitova advanced by beating fellow Czech Denisa Allertova 6-2 6-4.
Latvia’s Ostapenko overcame Serb Aleksandra Krunic 6-3 7-6 (7-9), while Bencic beat Luxembourg’s Mandy Minella 6-3 6-2 on day two of the final Grand Slam of the year.