Question: What was the partner of the team that faced the Guillermo García-López Albert Portas on Clay?
SQL: SELECT "Partner" FROM "2-12871566-3" WHERE "Surface" = 'Clay' AND "Opponents" = 'Guillermo García-López Albert Portas';

Question: What are the dates where the opponent was Guillermo García-López Albert Portas?
SQL: SELECT "Date" FROM "2-12871566-3" WHERE "Opponents" = 'Guillermo García-López Albert Portas';