Luis Suarez scored a hat-trick as Barcelona kept up their title push by thrashing 10-man Athletic Bilbao.
The visitors had goalkeeper Gorka Iraizoz sent off early on for bringing down the Uruguay forward, with Lionel Messi converting the penalty.
Neymar chipped a second before half-time, with Suarez and Ivan Rakitic making it 4-0 after the break.
Suarez slotted in Arda Turan's pass, then headed the sixth to leave Barca two points behind Atletico Madrid.
Barcelona's bid to retain their La Liga title stumbled during December and early January with a run of three draws in four matches either side of the Christmas break.
With leaders Atletico Madrid securing a fourth successive victory by beating Las Palmas 3-0 earlier on Sunday, Luis Enrique's side knew at kick-off that they could not regain top spot - and so it was all about a statement of intent.
Their job was made significantly easier by the horrendous defensive mix-up that allowed Suarez to nip in behind centre-back Xabier Etxeita and win the penalty that Messi converted.
Barcelona, though, took advantage of that early break to swat Athletic aside with some sumptuous football.
Messi, named the Ballon d'Or winner on Monday, only played for the first 45 minutes before being substituted amid concerns that he had suffered a minor muscle strain.
Suarez grabbed the opportunity to take centre stage, and become the leading scorer in Europe's top five leagues, with 29 goals in 29 games in all competitions this season - but he also got a whack in the face for his troubles.
Television pictures showed Etxeita glancing over towards Suarez before catching him with a forearm, well away from the ball. The defender may face retrospective action.
The competition for the Pichichi - the Spanish golden boot - intensified on Sunday, with all four of the leading contenders scoring.
After Cristiano Ronaldo and Karim Benzema had both taken their La Liga season totals to 16 by scoring twice each in Real Madrid's 5-1 win over Sporting Gijon, the pressure was on Neymar and Suarez to keep pace.
Both players responded positively, with Suarez providing three excellent second-half finishes to move to the top of the league goal charts on 18.
Suarez capitalised on Etxeita's hesitation to win the penalty from which Messi gave Barca the lead, before playing in Neymar to score his 16th La Liga goal of the season with a perfectly judged chip.
The Brazil forward returned the compliment by playing Suarez through to slide in a third goal early in the second half, and then showed wonderful footwork as he darted to the byeline and provided a low cut-back for Rakitic to make it four.
Suarez added a fifth with a stylish finish, controlling Arda's diagonal pass before nudging a shot beyond the goalkeeper, and secured the match ball with a header from Sergio Busquets' cross.
If it was a night to forget for Athletic keeper Iraizoz, spare a thought too for his team-mate Iker Muniain.
The 23-year-old forward was making his first league start since suffering cruciate knee ligament damage last April, and was keen to make an impact. Instead, his night was cut short through no fault of his own.
He had one opportunity to catch the eye, when he intercepted Gerard Pique's sloppy back pass and got the better of goalkeeper Claudio Bravo to set up Javier Eraso, who lifted the chance over.
Within seconds of that miss, Iraizoz had been sent off - and it was a visibly disappointed Muniain who was substituted to allow replacement goalkeeper Iago Herrerin to face Messi's penalty.
Athletic Bilbao and Barcelona meet again on Wednesday, this time at the San Memes Stadium, in the first leg of their Copa Del Rey quarter-final. After that comes a return to league action, with Barca travelling to Malaga next Saturday before Athletic host Eibar on Sunday.
Full Time Match ends, Barcelona 6, Athletic Club 0.
90:00 +1:58 Full timeFull Time Second Half ends, Barcelona 6, Athletic Club 0.
88:05Attempt saved. Iturraspe (Athletic Club) right footed shot from outside the box is saved in the top centre of the goal.
86:59 BookingBooking Gerard Piqué (Barcelona) is shown the yellow card for a bad foul.
86:55Gerard Piqué (Barcelona).
86:55Eraso (Athletic Club) wins a free kick in the attacking half.
84:35 BookingBooking Eraso (Athletic Club) is shown the yellow card for a bad foul.
84:30Javier Mascherano (Barcelona) wins a free kick in the defensive half.
84:30Foul by Eraso (Athletic Club).
84:21Attempt saved. Sabin (Athletic Club) right footed shot from the centre of the box is saved in the top centre of the goal.
81:49 Goal scoredGoal! Goal! Barcelona 6, Athletic Club 0. Luis Suárez (Barcelona) header from the centre of the box to the bottom left corner. Assisted by Sergio Busquets with a cross.
81:21Corner, Barcelona. Conceded by Iago Herrerín.
78:09Attempt missed. Neymar (Barcelona) right footed shot from outside the box is just a bit too high from a direct free kick.
77:07Neymar (Barcelona) wins a free kick in the attacking half.
77:07Foul by Eneko Bóveda (Athletic Club).
74:54Sergi Roberto (Barcelona) wins a free kick in the defensive half.
74:54Foul by San José (Athletic Club).
74:18Foul by Sergio Busquets (Barcelona).
74:18Eraso (Athletic Club) wins a free kick in the defensive half.
72:42Attempt missed. De Marcos (Athletic Club) right footed shot from outside the box is close, but misses to the right following a set piece situation.
Attempt blocked. Aymeric Laporte (Athletic Club) left footed shot from outside the box is blocked.
71:28Foul by Marc Bartra (Barcelona).
71:28De Marcos (Athletic Club) wins a free kick in the attacking half.
70:12Attempt saved. Neymar (Barcelona) right footed shot from the left side of the box is saved in the bottom right corner. Assisted by Sergi Roberto.
68:50 BookingBooking De Marcos (Athletic Club) is shown the yellow card.
68:45 SubstitutionSubstitution Substitution, Barcelona. Marc Bartra replaces Jordi Alba because of an injury.
68:00 Goal scoredGoal! Goal! Barcelona 5, Athletic Club 0. Luis Suárez (Barcelona) right footed shot from the left side of the six yard box to the centre of the goal. Assisted by Arda Turan.
62:17 SubstitutionSubstitution Substitution, Barcelona. Sergi Roberto replaces Ivan Rakitic.
62:06 SubstitutionSubstitution Substitution, Athletic Club. Iturraspe replaces Beñat.
61:11 Goal scoredGoal! Goal! Barcelona 4, Athletic Club 0. Ivan Rakitic (Barcelona) right footed shot from the left side of the six yard box to the centre of the goal. Assisted by Neymar.
60:26Attempt missed. Eraso (Athletic Club) left footed shot from the centre of the box is just a bit too high. Assisted by Sabin with a cross following a fast break.
58:57Corner, Barcelona. Conceded by Balenziaga.
57:29Neymar (Barcelona) wins a free kick in the attacking half.
57:29Foul by Eneko Bóveda (Athletic Club).
55:30 SubstitutionSubstitution Substitution, Athletic Club. Sabin replaces Iñaki Williams.
55:13Attempt missed. Ivan Rakitic (Barcelona) right footed shot from outside the box misses to the right. Assisted by Andrés Iniesta.
54:15Sergio Busquets (Barcelona) wins a free kick in the attacking half.
54:15Foul by De Marcos (Athletic Club).
50:10 BookingBooking Javier Mascherano (Barcelona) is shown the yellow card for a bad foul.
49:58Foul by Javier Mascherano (Barcelona).
49:58Iñaki Williams (Athletic Club) wins a free kick in the attacking half.
48:36Offside, Barcelona. Aleix Vidal tries a through ball, but Luis Suárez is caught offside.
46:21 Goal scoredGoal! Goal! Barcelona 3, Athletic Club 0. Luis Suárez (Barcelona) right footed shot from the centre of the box to the bottom right corner. Assisted by Neymar with a through ball.
45:00 SubstitutionSubstitution Substitution, Barcelona. Arda Turan replaces Lionel Messi.
45:00Second Half begins Barcelona 2, Athletic Club 0.
45:00 +1:17 Half timeHalf Time First Half ends, Barcelona 2, Athletic Club 0.
45:00 +0:46Corner, Athletic Club. Conceded by Jordi Alba.
45:00 +0:44Attempt blocked. Iñaki Williams (Athletic Club) right footed shot from outside the box is blocked.
45:00 +0:39Attempt blocked. Beñat (Athletic Club) right footed shot from outside the box is blocked. Assisted by Balenziaga.
45:00 +0:03Corner, Barcelona. Conceded by Eneko Bóveda.
40:56Attempt missed. Lionel Messi (Barcelona) left footed shot from outside the box is close, but misses to the left from a direct free kick.
39:47Lionel Messi (Barcelona) wins a free kick in the attacking half.
39:47Foul by San José (Athletic Club).
37:21Attempt missed. Luis Suárez (Barcelona) left footed shot from the right side of the box is too high.
35:01Offside, Barcelona. Lionel Messi tries a through ball, but Aleix Vidal is caught offside.
34:07Attempt missed. Lionel Messi (Barcelona) left footed shot from the centre of the box is too high. Assisted by Neymar.
31:59Foul by Neymar (Barcelona).
31:59Eneko Bóveda (Athletic Club) wins a free kick in the defensive half.
30:24 Goal scoredGoal! Goal! Barcelona 2, Athletic Club 0. Neymar (Barcelona) left footed shot from the left side of the box to the bottom right corner. Assisted by Luis Suárez following a fast break.
28:05Attempt missed. Aleix Vidal (Barcelona) right footed shot from the right side of the box is just a bit too high.
26:23Attempt missed. Neymar (Barcelona) left footed shot from the left side of the six yard box is too high. Assisted by Ivan Rakitic with a cross.
25:26Foul by Aleix Vidal (Barcelona).
25:26Balenziaga (Athletic Club) wins a free kick in the defensive half.
24:22Offside, Athletic Club. Iñaki Williams tries a through ball, but Eraso is caught offside.
22:43Attempt missed. Ivan Rakitic (Barcelona) right footed shot from the centre of the box is too high. Assisted by Neymar.
22:10Attempt missed. Luis Suárez (Barcelona) right footed shot from outside the box misses to the left following a corner.
21:44Corner, Barcelona. Conceded by Etxeita.
21:42Attempt blocked. Luis Suárez (Barcelona) left footed shot from the left side of the box is blocked. Assisted by Lionel Messi.
21:16Attempt blocked. Neymar (Barcelona) right footed shot from the centre of the box is blocked.
17:59Corner, Barcelona. Conceded by Etxeita.
17:55Attempt blocked. Neymar (Barcelona) right footed shot from the centre of the box is blocked.
15:42Corner, Athletic Club. Conceded by Claudio Bravo.
15:40Attempt saved. De Marcos (Athletic Club) right footed shot from a difficult angle on the right is saved in the centre of the goal. Assisted by Iñaki Williams.
14:49Attempt missed. Luis Suárez (Barcelona) right footed shot from outside the box is too high. Assisted by Ivan Rakitic.
11:23Offside, Barcelona. Jordi Alba tries a through ball, but Luis Suárez is caught offside.
10:01Offside, Barcelona. Luis Suárez tries a through ball, but Gerard Piqué is caught offside.
9:28Corner, Barcelona. Conceded by De Marcos.
6:24 Goal scoredGoal! Goal! Barcelona 1, Athletic Club 0. Lionel Messi (Barcelona) converts the penalty with a left footed shot to the bottom right corner.
5:51 SubstitutionSubstitution Substitution, Athletic Club. Iago Herrerín replaces Muniain.
3:10 DismissalDismissal Gorka Iraizoz (Athletic Club) is shown the red card.
3:03Penalty Barcelona. Luis Suárez draws a foul in the penalty area.
3:03Penalty conceded by Gorka Iraizoz (Athletic Club) after a foul in the penalty area.
1:53Attempt missed. Eraso (Athletic Club) left footed shot from the centre of the box is just a bit too high. Assisted by Muniain.
0:00First Half begins.
0:00Lineups are announced and players are warming up.
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