Second-seeded Emma Raducanu’s Citi Open run ended in a quarter-final loss to Liudmila Samsonova in Washington.
Despite a tight first set, Raducanu was eventually overpowered 7-6 (8-6) 6-1 by world number 60 Russia.
Samsonova saved four set points en route to clinching the first set before heading home in the second with nine aces and 33 winners for the match.
Raducanu proved to be her worst enemy as she struggled to match Samsanova’s strength, mustering just eight winners and a single ace to go along with 24 unforced errors.
In the ATP event, Britain’s No. 2 Dan Evans lost in three sets to Japan’s Yoshihito Nishioka in their quarter-final clash.
After losing the first set in a tiebreak, Evans rallied to win the second in convincing fashion.
However, he was unable to sustain that momentum in the third as the world No. 96 cruised to a 7-6 (7-5) 4-6 7-5 win.
Norrie will face Medvedev in the final in Mexico
Defending champion Cameron Norrie took on world number one Daniil Medvedev in the Abierto de Tenis Mifel final with a win over Felix Auger-Aliassime.
The British No. 1 battled for a 6-4 3-6 6-3 victory over the second seeded Canadian in two hours and 19 minutes in the second semi-final in Los Cabos, Mexico.
Norrie’s success, his first against Auger-Aliassime in five encounters, kept the third seed on course for a third ATP Tour title this year.
He will now face Medvedev, who beat fourth seed Miomir Kecmanovic 7-6 6-1 to secure the top spot in the world rankings until at least the end of the US Open next month.
Norrie told reporters: “You still want to defend the title but it’s complicated. The start was tough but I played very well after losing the second set.
“I try to play at my best level and it’s amazing to come back to the final. I love playing in Mexico.”