Norrie had lost his four previous meetings against Felix Auger-AliassimeBritish number one Cameron Norrie reached the Los Cabos Open final in Mexico after overcoming Felix Auger-Aliassime 6-4 3-6 6-3.
Defending champion Norrie will next face world number one Daniil Medvedev, who beat Serbia's Miomir Kecmanovic.
It was Norrie's first win against his Canadian opponent, who hit 17 aces to the Briton's two in the match.
At the Washington Open quarter-finals, there were defeats for British pair Emma Raducanu and Dan Evans.
"Felix has got me the last four times, so going into it I really wanted to win that one," Norrie said.
"Previous times I had match points, so I was thinking about that in the back of my mind. It's never easy."
His next opponent, Russian Medvedev, is playing in his first tournament since June following injury - and a ban on Russian players at Wimbledon.
But it will be his fourth final of the year after beating Kecmanovic 7-6 (7-0) 6-1.
It means he will go into this month's US Open - where he is the defending men's singles champion - assured of the world number one ranking.
Meanwhile in Washington, defending women's US Open champion Raducanu was beaten by Russia's Liudmila Samsonova 7-6 (8-6) 6-1.
After a tight first set in which Samsonova saved four set points, the world number 60 powered past the English teenager in the second.
Raducanu, 19, was looking to reach her first semi-final since last year's grand slam win.
Samsonova will play China's Wang Xiyu in the semi finals after the 21-year-old beat two-time Australian Open winner Victoria Azarenka.
The other semi-final features Estonia's Kaia Kanepi against Australia's Daria Saville.
British men's number two Evans, meanwhile, was beaten 7-6 (7-5) 4-6 7-5 by Japan's Yoshihito Nishioka in their quarter-final.
It was a fifth meeting for the two - and Nishioka has won all five matches.
Nishioka will face top seed Andrey Rublev in the semi-finals. Russian Rublev played twice on Friday in a congested fixture list caused by rain delays but overcame Americans Maxime Cressy and JJ Wolf.
Australia's Wimbledon runner-up Nick Kyrgios plays Sweden's Mikael Ymer in the other semi-final.
