Venus Williams has continued her remarkable season by winning a superb battle against Petra Kvitova to reach the US Open semi-finals for the first time in seven years.
After final defeats at the Australian Open and Wimbledon, the 37-year-old finds herself within two victories of a first grand slam title on home soil since 2001.
She was pushed all the way in a thrilling duel on Tuesday, eventually prevailing 6-3 3-6 7-6 (7/2) in a deciding tie-break after two hours and 35 minutes.
"It feels amazing. It's so wonderful to see her back and playing amazing. I'm so fortunate to have won that match. It came down to the wire and I hope we have more matches like that," Williams said.
"I try to tell myself to enjoy the competition and enjoy the battle and I think I was able to do that tonight."
Williams' victory also ensures she will return to the top five in the rankings for the first time in six years, irrespective of the result of her next match against fellow countrywoman Sloane Stephens.
The pair completed half of what could be an American clean sweep of the semi-finals, with CoCo Vandeweghe and Madison Keys playing their matches on Wednesday.
Stephens reached her first grand slam semi-final since 2013 by beating 16th-seeded Anastasija Sevastova 6-3 3-6 7-6 (7-4).
The 83rd-ranked Stephens has won 13 of her past 15 matches.
Sevastova beat Maria Sharapova in the fourth round and was trying to reach the first major semi-final of her career.
She received treatment from a trainer late in the first set at Arthur Ashe Stadium on Tuesday for a problem with her upper right leg.
Stephens went 11 months between tournaments because of surgery on her left foot in January, returning to competition at Wimbledon in July.
Her only previous trip to the final four at a major tournament came at the Australian Open four years ago.
"I'm getting teary-eyed. This is just incredible. When I started my comeback at Wimbledon I could have never even have dreamed of something like this happening, making the semi-finals of my home slam, my favourite tournament," Stephens said.