New York - Samantha Stosur lost the battle but won the war, surrendering an historic second-set tiebreaker but recovering to beat Maria Kirilenko 6-2, 6-7 (15/17), 6-3 on Sunday to reach the US Open quarter-finals.
Russia's Kirilenko prevailed in what the WTA said was the longest women's singles tiebreaker at a Grand Slam tournament to knot the fourth-round match at a set apiece.
The 17/15 duel is destined to join the list of epic Grand Slam tiebreakers, including the 18/16 fourth-set tiebreaker that John McEnroe won over Bjorn Borg in the 1980 Wimbledon final - in which Borg eventually triumphed.
Stosur failed on five match points in the tiebreaker, which Kirilenko finally claimed on her sixth set point when Stosur netted a forehand.
Until then, the two had not been separated by more than a point throughout. Stosur took a 1-0 lead and Kirilenko didn't get her nose in front until she took a 6-5 lead for her first set point.
Three line calls in Stosur's favor were overturned on challenges by Kirilenko - including two on the same match point at 14/13.
"Obviously I knew it ws pretty long," Stosur said of the tiebreaker, which stretched the second set to one hour and 24 minutes. "I lost track of the score, I didn't know at one point if I should be serving or receiving.
"With all the challenges it was super-exciting. The crowd was into it... I couldn't hear myself think."
Stosur had already entered the record books this week when she toiled for three hours and 16 minutes to get past Nadia Petrova 7-6 (7/5), 6-7 (5/7), 7-5 in the third round - the longest recorded women's singles match at the US Open since the tiebreak era began in 1970.
According to the WTA, the longest prior Grand Slam tiebreaker on record for women was a 16-14 duel in a 1999 French Open first-round match between Stephanie Foretz and Nathalie Dechy.