Two-time women's champion Elina Svitolina has crashed out of the Italian Open, while a knee injury has forced Serena Williams to pull out of the tournament.
Fifth seed Svitolina lost 6-4,1-6, 7-5 against Victoria Azarenka in the second round, while Serena announced her withdrawal just before her match against older sister Venus.
Czech fourth seed Karolína Plisková also advanced to the third round along with Australian eighth seed Ashleigh Barty.
In the men's competition, world no. 5 Alexander Zverev suffered a shock 7-5, 7-5 defeat to Italian wildcard Matteo Berrettini, while Belgian David Goffin rallied from a set down to beat Stan Wawrinka 4-6, 6-0, 6-2.
Ninth seed Marin Cilic, seventh seed Juan Martin Del Potro, Australian Nick Kyrgios and Portugal's Joao Sousa are also through to the second round.
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