The judge in Valencia remanded 36-year-old Juan Cuenca and ex-director of volleyball CAV Murcia after questioning in a closed-door investigation into the killing of the Dutch couple, said a court official who asked not to be named.
Spanish media reported that the suspect was the former manager of a volleyball club in which the dead woman, Ingrid Visser, had played.
The bodies were found buried in a lemon grove in Murcia, southeastern Spain. Police said they arrested three people, including two Romanians, in Valencia.
The court in Valencia was expected to question the two other suspects on Wednesday.
Police were waiting for the results of DNA tests to confirm whether the bodies were those of Visser, 35, and her partner Lodewijk Severein, 57.
The couple disappeared on May 13 shortly after checking into a hotel in Murcia.
The city's police chief Cirilo Duran told a press conference that they had suffered a violent death.
Spanish media, citing sources close to the investigation, reported that the two were found in a shallow grave, cut into pieces, and may have been tortured.
Duran said investigators suspected the couple had "business disagreements" with the suspects that had led to the killing.
Visser was part of the Netherlands's gold medal-winning team at the European Championship in 1995 and played for a volleyball team in Murcia between 2009 and 2011.
A spokesperson for the families, Miriam Van de Velde, has criticized Spanish media for publishing "unnecessary details" of the case, reported El Mundo newspaper on Tuesday.
This was chiefly because "the family had yet to receive official information," said the spokesperson.