Dominika Cibulkova has caused the first shock of this year's US Open by recording a three-set win over Ana Ivanovic.
The world number 50 withstood a mid-game fightback from the seventh seed to seal a 6-3 3-6 6-3 triumph at Flushing Meadows.
Ivanovic started the contest in fine style, breaking her opponent's serve at the first time of asking, but Cibulkova, who has been as high as 10th in the world rankings, stormed back to win four games in a row to take the opener.
The Slovak soon stole a march at the start of the second as Ivanovic struggled for consistency from the back of the court, but after facing a 3-1 deficit, she stormed back with five successive games to force a decider.
That became six at the beginning of the third as Ivanovic broke immediately, but it was Cibulkova's turn to run off a number of consecutive games as she won four in a row to move to the brink of a place in the last 64.
Ivanovic continued to fight, but Cibulkova showed few nerves in serving the match out to see off the former world number one.
