Match ends, Barcelona 3, Alavés 0.
Lionel Messi scored twice as Barcelona got their La Liga title defence off to a winning start with a deserved, hard-fought victory over Alaves.
Messi fired a fantastic free-kick under the wall to open the scoring - Barcelona's 6,000th La Liga goal.
Half-time substitute Philippe Coutinho then cut inside to curl home a second.
And Messi controlled Luis Suarez's pass with his chest, beat two defenders and steered a low shot into the bottom corner of the net in injury time.
Messi, now Barcelona's captain after Andres Iniesta's move to Japan, had also hit the woodwork twice - with a free-kick that deflected off the bar and another effort coming off the post.
He has scored in 15 consecutive La Liga seasons.
Barcelona were made to work hard for the win by Alaves, who offered little going forward and only had three shots, none on target, and 21% possession.
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Messi, who also hit Barcelona's 5,000th La Liga goal eight years ago, has scored 6.4% of the club's top-flight goals ever.
Barcelona, who brought on summer signings Arthur and Arturo Vidal for league debuts, beat Sevilla 2-1 in the Spanish Super Cup on Sunday.
Real Madrid get their league campaign under way on Sunday, at home to Getafe (21:15 BST). Atletico Madrid visit Valencia on Monday (19:00 BST).
Elsewhere in La Liga, Villarreal midfielder Santi Cazorla made his first appearance since October 2016 for Arsenal following a serious Achilles tendon injury. Unfortunately for him, his side lost 2-1 at home to Real Sociedad.
- 1ter Stegen
- 2Nélson SemedoSubstituted forCoutinhoat 45'minutes
- 5BusquetsSubstituted forVidalat 85'minutes
- 11DembéléSubstituted forArthurat 77'minutes
- 6MaripánBooked at 41mins
- 16TorresBooked at 10minsSubstituted forMarínat 68'minutes
- 19García Sánchez
- 23Rodríguez MenéndezSubstituted forBastónat 68'minutes
- 7SobrinoSubstituted forFranco Alvizat 71'minutes
- 14Franco Alviz
- 15Navarro Jiménez
- José María Sánchez Martínez
- Shots on Target
Second Half ends, Barcelona 3, Alavés 0.
Goal! Barcelona 3, Alavés 0. Lionel Messi (Barcelona) left footed shot from the centre of the box to the bottom left corner. Assisted by Luis Suárez.
Offside, Barcelona. Ivan Rakitic tries a through ball, but Lionel Messi is caught offside.
Attempt saved. Lionel Messi (Barcelona) left footed shot from the centre of the box is saved in the centre of the goal. Assisted by Sergi Roberto.
Hand ball by Adrián Marín (Alavés).
Foul by Arthur (Barcelona).
Manu García (Alavés) wins a free kick in the defensive half.
Dangerous play by Luis Suárez (Barcelona).
Adrián Marín (Alavés) wins a free kick in the defensive half.
Substitution, Barcelona. Arturo Vidal replaces Sergio Busquets.
Goal! Barcelona 2, Alavés 0. Coutinho (Barcelona) right footed shot from the centre of the box to the centre of the goal. Assisted by Arthur.
Attempt saved. Coutinho (Barcelona) right footed shot from the centre of the box is saved in the bottom left corner. Assisted by Lionel Messi with a through ball.
Corner, Barcelona. Conceded by Guillermo Maripán.
Attempt missed. Adrián Marín (Alavés) right footed shot from the centre of the box is close, but misses to the left. Assisted by Ibai Gómez following a set piece situation.
Foul by Ivan Rakitic (Barcelona).
Burgui (Alavés) wins a free kick in the attacking half.
Samuel Umtiti (Barcelona) wins a free kick in the defensive half.
Foul by Manu García (Alavés).
Substitution, Barcelona. Arthur replaces Ousmane Dembélé.