Athletic Bilbao B
Bilbao Athletic, officially named Athletic Club "B", is the reserve team of Athletic Bilbao, a football club based in Bilbao, in the autonomous community of Basque Country. The team will play in the Segunda División B in the 2018–19 season. Founded in 1964, the team holds home matches at the small stadium attached to the club's training facility at Lezama, or occasionally at San Mamés Stadium, with its 53,500-seat capacity, for important fixtures.
Basque derby
By the 1909 event, the "Recreation Club" had evolved into "San Sebastián Foot-Ball Club" but aligned with Club Ciclista de San Sebastián to meet the entry requirements. They defeated Athletic in the opening round and went on to win the trophy.
The following year, the club was renamed "Sociedad de Foot-Ball de San Sebastián" and had received royal patronage, entitling it to add the prefix "Real". However a dispute occurred over the entitlement of Real Sociedad to claim the honour of champions, and two separate competitions were held (both of which were later declared official, meaning there are two 1910 winners). Although Real Sociedad hosted their version of the competition at their Ondarreta ground, once again they did not meet the requisite statutes and their players joined with another club to participate, this time "Vasconia Sporting Club". Once more it was a three-team league involving Athletic Bilbao and Madrid, with Athletic winning both of their matches to win the cup, with the decisive win being over Vasconia who are thus listed as runners-up (and in any case they beat Madrid to confirm that status).