Robert Lewandowski shrugged off a string of missed opportunities to earn Barcelona a 2-1 win over Athletic Bilbao on Saturday in La Liga.
Players boarded a barge known as the 'Gabarra' and sailed 13 kilometres down the river from the affluent town of Getxo to the Bilbao city hall, where the party continued.
Athletic have been through years of heartache, having lost their previous six consecutive Spanish cup finals and a Europa League final to Atletico Madrid in 2012.
Rodrygo fired La Liga leaders Real Madrid to a 2-0 win over Athletic Bilbao with a superb brace on Sunday to restore their eight-point advantage on Barcelona.
Bilbao are the second most successful team in the history of the Copa del Rey, their 23 titles behind only Barcelona's 31, their most recent coming in 2020-21.
Inaki Williams raced back from Africa to face Barcelona in the Copa del Rey and sent Athletic Bilbao into the semi-finals by scoring a crucial goal in their 4-2 extra-time triumph on Wednesday.
Winger Viktor Tsygankov put the hosts ahead 10 minutes after half time but Inaki Williams scored 12 minutes later to claim a point for the away side
Arsenal scrape into the last 16 of the Europa League despite a 2-1 second-leg defeat by Ostersunds, but football was marred by violent clashes at the match between between Athletic Bilbao and Spartak Moscow which left a police officer dead.
Aymeric Laporte announces he is leaving Athletic Bilbao with Premier League leaders Manchester City primed to break their transfer record to sign the French defender.
Barcelona boss Luis Enrique launched a staunch defence of his players after they came from behind without the injured Lionel Messi to beat Bayer Leverkusen 2-1 on Tuesday.
Real Madrid moved top of La Liga as Karim Benzema struck in each half to earn the visitors a 2-1 win over Athletic Bilbao at San Mames on Wednesday.
Barcelona start the defence of their La Liga title Athletic Bilbao while Real Madrid kick-off the new season against Sporting Gijon.
Athletic Bilbao win the Spanish Supercopa after beating Barcelona by an aggregate score of 5-1.
The treble-winning FC Barcelona stars show the Champions League, La Liga and Copa del Rey trophies through the Catalan capital.
Bayern Munich coach Pep Guardiola compares Lionel Messi to Brazil legend Pele as he backs his former club Barcelona to win the Champions League.
