Real Sociedad are competing in their eighth Copa del Rey final, having lost the 1988 final to Barcelona. Athletic Bilbao are competing in their 38th final, having lost to Barcelona in 2015. In reaching the final, both teams were assured qualification for the four-team 2020–21 Supercopa de España. In the 1910 Copa del Rey, the two clubs participated in the three-team group of the UECF competition along with Madrid FC. The decisive match was between the Basque teams, but as it was not a final in the traditional knockout format and the newly-formed Real Sociedad were playing under the name 'Vasconia' for licensing reasons, it is not widely recognised as an equivalent to their meeting 110 years later.
Indefinite delay
Around the time of the original date for the final, the Spanish federation had indicated they would grant the designated Europa League place to Athletic Bilbao should the match not be played within the period of 2019–20, as Real Sociedad were likely to qualify for at least the Europa League and possibly the Champions League via the table. However, on 30 AprilUEFA stated that the final must be played by 3 August to activate the designated qualification place, otherwise this would revert to the team finishing 7th in La Liga. Due to the COVID-19 pandemic, it would be very unlikely that any final played by then would allow spectators into the stadium, a factor both clubs had declared was essential when it was initially postponed. Athletic Bilbao submitted a formal protest against UEFA's instruction, and on 4 May both teams officially reiterated their stance to delay the match until such a time as supporters would be able to attend it. When the league resumed in June 2020, the form of both clubs was poor: Athletic Bilbao collected 14 points from 33 available while Real Sociedad gained only 10 points and slipped down the table; however, five of those came in the last three matchdays, including one from an 88th-minute equaliser against Atlético Madrid on the final day to keep them just above Granada and Getafe – they finished sixth and qualified for the Europa League group stage, the same status as would have been afforded the Copa winner. Athletic's challenge had already fallen short and they placed eleventh.
