This is Anett Kontaveit's (#152) first ever foray into the fourth round of the US Open and for any grand slam as well. She's another up-and-coming player from Estonia.
She had to go through qualifying to reach the main round and her win today in the third round against American Madison Brengle (#47) 62 36 60 was her third consecutive match these two weeks.
In the first round, she defeated Australian Casey Dellacqua (#60) 75 62, then dispatched seeded Russian player Anastasia Pavlyuchenkova (#31) 75 64.
Her trip ended in the fourth round though as she lost to the legendary champion Venus Williams (#23) 62 61.