NEW YORK (AP) Venus Williams went from down and out to a point from victory, then back again. In the end, she couldn't quite get past a woman a dozen years younger and never before at this stage of a Grand Slam tournament.
Williams failed to convert a match point and lost 4-6, 6-4, 7-6 (3) to 10th-seeded Karolina Pliskova of the Czech Republic in the fourth round of the U.S. Open on Monday, despite vociferous support from the Arthur Ashe Stadium crowd down the stretch.
''I really played the perfect point there,'' the sixth-seeded Williams said about her chance to end things while up 5-4 in the third set, and Pliskova serving at 30-40, ''and she managed to stay alive.''
At 36, Williams would have been the oldest woman to reach the quarterfinals at any major since Martina Navratilova was 37 at Wimbledon in 1994.
Williams made it that far at Flushing Meadows a year ago, before losing to her younger sister Serena. This time, they had been on course for an all-in-the-family showdown in the semifinals; Serena followed Venus in Ashe and beat Yaroslava Shvedova 6-2, 6-3 in the fourth round for her 308th Grand Slam match victory, breaking a tie with Roger Federer for most in the Open era, which dates to 1968.
Pliskova managed, just barely, to make it to her first Grand Slam quarterfinal at age 24. Until this tournament, she never had been past the third round in 17 appearances at majors.
''I was prepared that I'm going to play Venus - it's going to be tough, because all the people are cheering for her,'' said Pliskova, who leads the tour in aces in 2016 and produced eight in this match.
It took her a while to finish off this one, despite going up an early break in the third set and leading 4-2. Just as it seemed she would run away with it, Williams turned things around enough to go up 5-4 and hold a match point. But Pliskova erased that with a swinging forehand volley - the sort of shot Williams loves to hit - and followed it up with another aggressive forehand winner.
Then Pliskova broke to lead 6-5 and served for the match, getting three chances to close it at 40-love. After Pliskova frittered away one with a double-fault, Williams steeled herself and stepped up, smacking a volley winner, cross-court backhand winner and two forehand winners to break back for 6-all.
''To be honest,'' Pliskova said, ''it was really difficult ... when I lost my serve.''
Somehow, though, she pulled herself together enough to get through the tiebreaker as Williams faltered.
''In the `breaker, I went for a little bit more,'' Williams said, ''but I didn't put the ball in enough.''
Pliskova will face 92nd-ranked Ana Konjuh, an 18-year-old from Croatia who upset No. 4 Agnieszka Radwanska 6-4, 6-4 by compiling a 38-9 edge in winners. Also reaching the quarterfinals with a victory Monday was 2014 French Open runner-up Simona Halep, who eliminated No. 11 Carla Suarez Navarro 6-2, 7-5. Now it's Halep's turn to try to deal with the serve of Serena Williams, who reached a tournament-best 126 mph, delivered 11 aces and won 28 of 30 first-serve points against Shvedova.
In men's action, 2009 champion Juan Martin del Potro became the lowest-ranked man in the U.S. Open quarterfinals in 25 years, advancing when No. 8 seed Dominic Thiem stopped in the second set because of an injured right knee.
Del Potro missed 2 1/2 years' worth of major tournaments because of a trio of operations on his left wrist, so he's ranked only 142nd. Jimmy Connors was 174th when he made a stirring run to the semifinals in New York at age 39 in 1991.
The 2012 title winner at Flushing Meadows, Andy Murray, eased into the quarterfinals for the 22nd time in his past 23 majors, beating No. 22 Grigor Dimitrov 6-1, 6-2, 6-2 at night. Murray now faces 2014 runner-up Kei Nishikori, who advanced by beating No. 21 Ivo Karlovic 6-3, 6-4, 7-6 (4). Murray defeated Nishikori in the semifinals of the Rio Olympics last month en route to an unprecedented second consecutive singles gold medal.
Del Potro has been playing as well as ever lately, winning the silver in Rio and picking up recent victories over Novak Djokovic, Rafael Nadal and Stan Wawrinka.
In the quarterfinals, del Potro's opponent will be No. 3 Wawrinka, a 6-4, 6-1, 6-7 (5), 6-3 winner against Illya Marchenko.
''He will be the favorite to win in that match,'' said del Potro, who beat Wawrinka at Wimbledon.
''But,'' del Potro added, ''anything can happen in this event for me. I got the power from the crowd in every match.''
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