Rafael Nadal was beaten in what might prove to be the final match of his career as the start of his Davis Cup retirement party fell flat.
Spanish great Nadal, who has won 22 Grand Slam titles, will end his tennis playing journey after the men's team event in Malaga.
It had been unclear whether the 38-year-old former world number one would be ready to play in the singles.
But Nadal was selected by Spain captain David Ferrer, even though he had not played competitively for over three months.
The move backfired in front of a partisan Spanish crowd as Nadal lost 6-4 6-4 to Botic van de Zandschulp, who admirably maintained his composure in testing conditions to put the Netherlands ahead in the tie.
If Spain are unable to recover the 1-0 deficit in the best-of-three encounter, there will be no other opportunity for Nadal to take to the court as a professional again.
