Great Britain went 1-0 down in their Davis Cup World Group tie in Spain as Liam Broady was beaten in straight sets by Albert Ramos-Vinolas.
Broady, ranked 165 and making his Davis Cup debut, fought well but lost 6-3 6-4 7-6 (8-6) to the world number 21.
Australian Open semi-finalist Kyle Edmund was not chosen by captain Leon Smith because of a hip injury.
GB’s Cameron Norrie faces Roberto Bautista Agut in Friday’s second singles rubber on clay in Marbella.
Broady, 24, served for the third set at 6-5 and had a set point in the tie-break that followed, but Ramos-Vinolas, 30, closed out victory for the hosts when Broady was stretched too far by a forehand return.