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.

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.