The tenth seed won 6-0, 6-1 win in 65 minutes as she bids to win her first Major at Flushing Meadows following defeat in the final five years ago.
Elsewhere, 17-time Major winner Roger Federer sealed a comfortable win to reach the last eight, and Tomas Berydch and Gael Monfils eased into the quarter-finals.
Here is a selection of the best Twitter reaction from the professionals to all the action in New York on Tuesday.
1Oth seed Caroline Wozniacki (@CaroWozniacki) is thrilled to beat Sara Errani and reach the US Open last four: “So happy to be back in the semis at the usopen!! Thank you everyone for the amazing support!”
Meanwhile, in the men’s draw, France star Gael Monfils (@Gael_Monfils) is loving the support from his fans: ” RT ‘@martinsolveig: @Gael_Monfils c’est fait! Yeah! Keep it going bro’ merciii”
Czech sixth seed Tomáš Berdych (@tomasberdych) is hearing voices – could it be the heat? “I heard the voice at Satchmo Stadium today. Gently whispering ‘And I think to myself what a wonderful world’ #louisarmstrong #USOpen”
17-time Major winner Serena Williams (@serenawilliams) posts a picture of cooling towels and a all-round cool guy: “Mission cooling towels”
Tennis legend Patrick McEnroe (@PatrickMcEnroe) gives his thoughts as he rivals his famous brother John for punditry:
“Tennis done before 11pm @usopen tonight thx to great performances from Fed and Woz. Time to catch up on some sleep tennis fans”
Finally, famous tennis coach Nick Bollettieri (@NickBollettieri ) congratulates Shuai Peng on a great achievement: “Congrats to Shuai Peng for reaching the @usopen semis. Reminded me of the great @MonicaSeles10s w/2 hands playing inside the baseline.”
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