Jamie Murray and Bruno Soares lost their Citi Open men's doubles semi-final to top seeds John Peers and Henri Kontinen on a third-set tie-break.
Britain's Murray and Brazil's Soares, the third seeds, were beaten 6-7 (4-7) 7-5 10-8 to Australia's Peers and Finland's Kontinen in Washington.
Murray and Soares saved seven match points in Friday's quarter-final win over James Cerretani and Marc Polmans.
But Peers and Kontinen ended their bid despite losing the opening set.
Kontinen is second in the ATP men's doubles rankings, with Peers third, 31-year-old Murray fifth and Soares sixth.