American top seeds Jessica Pegula and Taylor Fritz suffered semifinal defeats at the Washington Open on Saturday but Coco Gauff kept the star spangled banner flying by earning a place in Sunday's final.
Greek fourth seed Maria Sakkari upset top seed Pegula to capture her third victory in 26 hours and she will face another home favorite in the final after Gauff defeated Russian Liudmila Samsanova, the defending champion, in straight sets.
Fritz fell to Tallon Griekspoor 3-6, 6-3, 6-2 and the Dutchman will play for the title against Britain's Dan Evans, who beat Bulgaria's Grigor Dimitrov 6-3, 7-6 (7-4).
Ninth-ranked Sakkari, forced to play twice Friday due to rain on Thursday at the WTA and ATP hard court event, reached her first final since losing to Pegula last October at Guadalajara.
"It would have been ideal if I could be off the court an hour earlier," Sakkari said. "But at the end I got the win which is what I wanted the most."
Sakkari, who reached her seventh career final, won her only WTA title in 2019 at Rabat.
Pegula, the 2019 Washington champion, was denied her fifth career final but will match her career high of third in the world rankings next week.
Sakkari improved to 5-3 in her career rivalry with Pegula, who won their most recent prior meeting in February's Doha semifinals.
Sakkari dominated the first set and went up 4-1 in the second but Pegula broke Sakkari in the seventh game and held to pull level at 4-4.
A double fault handed Pegula a break chance in the ninth game and Sakkari swatted a forehand wide for a 5-4 edge. The American then held to force a third set.
"Things were tricky in the second set," Sakkari said. "In the third, I just tried to stay in the present. I tried to overcome myself and take it as a new challenge."
Sakkari broke early in the third set and again in the final game on a backhand winner to advance after two hours and three minutes.
Third-seeded Gauff was in dominant form as she won the opening set against Samsonova without facing a break point.
She then took a 2-1 lead in the second set, winning her fifth break point of a marathon game with a volley winner before completing a 6-3, 6-3 win to reach her second final of the year.
"She's a server and she has an amazing forehand so I wanted to see how I would do upon that battle and I think I did pretty well," said Gauff.
Gauff has lost four of her five meetings with Sakkari but says she has learned from those losses.
"She's an incredible player. She has been the top of the game for a long time and it's going to be a difficult match," she said.
- Dutchman's top-10 win -
Fritz, the highest-ranked American at ninth in the world, won the first set 6-3 after a break in the second game.
But 12th seed Griekspoor fought, breaking when he was 4-3 up and forcing a third set, which was close fought until Griekspoor made the most of Fritz's errors to break in the fifth game.
The Dutchman won the last five games, with 20 of the 27 points, to grab his first win against a top-10 foe and give himself a chance at a third title this year.
"The first Top 10 win was something I was really looking for. To beat Taylor playing at home is pretty special" said the Dutchman.
"My serve is going really well this week; it's getting some pace, whether it's during the day or during the night. I'm moving great and the body is great, so there's not much to complain about," he added.
The 33-year-old Evans, who becomes the tournament's first British finalist since Andy Murray 17 years ago, produced some inspired and aggressive tennis in his win after playing two matches on Friday.
After taking the first set, 30th-ranked Evans was pushed hard by by Dimitrov but emerged triumphant from the second set tie-break thanks to a magnificent drop shot to get to match point, which he won with a cross-court volley.