Mason (Ohio), Aug 13 : Reigning US Open champion Emma Raducanu will take on 23-time singles grand slam winner Serena Williams in the first round of the Western & Southern Open, which is the last major stop before action moves to Flushing Meadows for the last major of the year. World No.1 Iga Swiatek tops the 56-player singles draw of the second WTA 1000 tournament of the summer hard-court season. The top eight seeds will receive byes into the second round. Joining Swiatek in the top half of the draw are No.3 Paula Badosa, No.5 Ons Jabeur and No.8 Garbine Muguruza. Simona Halep, Coco Gauff, Belinda Bencic and Wimbledon champion Elena Rybakina are also in the star-spangled top half. No.2 Anett Kontaveit anchors the bottom half of the draw, along with No.4 Maria Sakkari, No.6 Aryna Sabalenka and No.7 Jessica Pegula, according to wtatenis.com. Playing in her last WTA Tour tournament before her final goodbye at the US Open, Williams will open her tournament against Raducanu on August 15. It will be the first meeting between the two. Serena heads to Cincinnati coming off her first win of the season, at the National Bank Open before losing to Belinda Bencic in the second round. Raducanu fell to Camila Giorgi in her opening hurdle in Toronto. The winner will face either Victoria Azarenka or Kaia Kanepi. Venus Williams, a wild-card entry, will face No.14 Karolina Pliskova in the first round. A champion in 2016, Pliskova holds a 2-1 record against Venus and is coming off a strong week in Toronto. Meanwhile, two former US Open champions will look to get more matches under their belt ahead of New York. Japan's Naomi Osaka, who was forced to retire in Toronto due to a back injury, will open her tournament against Zhang Shuai. Bianca Andreescu faces Giorgi in the first round. /IANS