Serena Williams defeated No. 8 seed and 2016 U.S. Open runner-up Karolina Pliskova 6-4, 6-3 on Tuesday in the U.S. Open quarterfinals. Williams advances to play in her 36th major semifinal on Thursday.
After defeating sister Venus, a two-time U.S. Open champion, in the third round at Arthur Ashe Stadium on Friday, Williams secured a 6–0, 4–6, 6–3 win over Kaia Kanepi on Sunday to advance to Tuesday's quarterfinals.
Williams entered the match as the tournament's No. 17 seed after being given a seeding boost by officials after her maternity leave. Williams was ranked 26th when she received her No.