New York: Hard-hitting Czech Karolina Pliskova toppled two-time champion Venus Williams 4-6, 6-4, 7-6 (7/3) on Monday to reach her first Grand Slam quarter-final at the US Open.
Pliskova, who had never before made it past the third round of a major in 17 prior attempts, saved a match point en route to a victory which scuppered a possible semi-final clash between Williams and her sister Serena.
The 36-year-old Williams was vying to become the oldest woman to reach the US Open quarters in the Open Era.
But the in-form Czech -- who shocked world number two Angelique Kerber in the final at Cincinnati in August -- settled her own late nerves to pull off the upset in front of a partisan Arthur Ashe stadium crowd.
"I was prepared that I`m going to play Venus, it`s going to be tough because people will be cheering for her," Pliskova said.
Williams was philosophical about her failure to convert a match point against Pliskova`s serve in the 10th game of the third.
"She had a great serve," Williams said. "She hit another great shot and I still played a great defensive shot. I did the best I could on that.
"Whenever you have a match point on someone else`s serve, it`s a little bit of an asterisk. I really have no regrets on that." Pliskova then broke Williams for a 6-5 lead -- with the help of a favorable net cord bounce.
Serving for the match and up 40-0, however, Pliskova couldn`t close it out. A double fault followed by four strong points from Williams sent it to the tiebreaker.
"To be honest it was very difficult after I lost my serve for six-all," Pliskova admitted. "She played a very good game."