Match ends, Athletic Club 2, Barcelona 5.
Lionel Messi inspired Barcelona as they moved within a point of La Liga leaders Real Madrid after winning a breathless encounter at Athletic Bilbao.
Messi's deflected free-kick, and a precise finish into the bottom corner from Luis Suarez put Barca in control.
Athletic's Mikel Rico stroked in after half-time, before Oscar De Marcos's own goal and Neymar put Barca 4-1 up.
Home striker Aritz Aduriz hit a fourth goal in seven minutes for 4-2, then Barca's Pedro tapped in a late fifth.
After opening the scoring, Argentina captain Messi turned provider to help create each of Barcelona's other four goals.
Neymar could have added a sixth, shooting straight at Athletic keeper Gorka Iraizoz when clean through, as Barca showed little mercy on a home side reduced to 10 men for the final 15 minutes.
Athletic defender Xabier Etxeita was sent off for a crude challenge on former Liverpool forward Suarez.
But, even with 11 men, the home side did not look capable of preventing a comfortable win for the visitors.
Coach Luis Enrique's position also came under scrutiny as that insipid performance saw Barca trail arch-rivals Real Madrid in the Spanish title race.
However, the Catalan club have won their last five league matches - nine across all competitions - to strengthen their ambitions of regaining the title from Atletico Madrid.
The defending champions, who are third, blew open the title race with a 4-0 home win against Real in Saturday's Madrid derby.
And that heavy defeat for Real, coupled with Barca scoring 21 in their last five wins, means Luis Enrique's side now have a superior goal difference than their rivals - which could prove vital in the title race.
Elsewhere, Valencia moved up to fourth with a 2-1 victory at Espanyol, leapfrogging Sevilla who lost 2-1 at Getafe.
- 10De Marcos
- 16EtxeitaBooked at 75mins
- 24BalenziagaBooked at 40minsSubstituted forAurtenetxeat 52'minutes
- 6San José
- 17Rico Moreno
- 14SusaetaSubstituted forEtxebarria Urkiagaat 69'minutes
- 29López CabreraBooked at 69mins
- 19MuniainSubstituted forGurpegiat 78'minutesBooked at 90mins
- 7Etxebarria Urkiaga
- 13Herrerín Buisán
- 22Alves da SilvaBooked at 45minsSubstituted forCorreiaat 69'minutes
- 6HernándezSubstituted forRafinhaat 74'minutes
- 9SuárezSubstituted forPedroat 80'minutes
- 1ter Stegen
- Antonio Miguel Mateu Lahoz
- Shots on Target
Second Half ends, Athletic Club 2, Barcelona 5.
Foul by Pedro (Barcelona).
Mikel Rico (Athletic Club) wins a free kick in the defensive half.
Carlos Gurpegi (Athletic Club) is shown the yellow card.
Corner, Barcelona. Conceded by Óscar De Marcos.
Attempt saved. Neymar (Barcelona) left footed shot from the centre of the box is saved in the centre of the goal. Assisted by Pedro.
Attempt saved. Neymar (Barcelona) right footed shot from outside the box is saved in the top centre of the goal. Assisted by Pedro.
Offside, Barcelona. Sergio Busquets tries a through ball, but Lionel Messi is caught offside.
Offside, Barcelona. Gerard Piqué tries a through ball, but Pedro is caught offside.
Goal! Athletic Club 2, Barcelona 5. Pedro (Barcelona) right footed shot from very close range to the centre of the goal. Assisted by Sergio Busquets.
Substitution, Barcelona. Pedro replaces Luis Suárez because of an injury.
Offside, Barcelona. Rafinha tries a through ball, but Luis Suárez is caught offside.
Substitution, Athletic Club. Carlos Gurpegi replaces Iker Muniain.
Rafinha (Barcelona) wins a free kick in the defensive half.
Foul by Mikel Rico (Athletic Club).
Delay over. They are ready to continue.
Delay in match Luis Suárez (Barcelona) because of an injury.
Xabier Etxeita (Athletic Club) is shown the red card for fighting.
Luis Suárez (Barcelona) wins a free kick in the defensive half.