Barcelona maintained their unbeaten start to the La Liga season with a hard-fought win at Athletic Bilbao.

Lionel Messi somehow hit the post after going round Bilbao goalkeeper Kepa, but stroked in the opener on 36 minutes.

Bilbao dominated the second half, with Raul Garcia heading against the bar and Aritz Aduriz drawing a sharp save from Barca goalkeeper Marc Andre ter-Stegen.

But the home side were caught on the counter late on as Paulinho, who hit the bar in the first half, slotted in.

Ernesto Valverde’s side have scored 28 goals and conceded just three so far this campaign, but this victory was based on a solid goalkeeping performance by German Ter-Stegen.

The former Borussia Monchengladbach keeper played superbly, thwarting Aduriz with a stunning left-handed save in the first half when the veteran striker had broken clear.

Bilbao, though, were wasteful with the ball in promising positions as Inigo Cordoba twice struck efforts off target from inside the area, and Garcia drove a shot wide as well.

Aduriz forced Ter-Stegen into further fine saves in the second half and Inaki Williams came close too as the hosts failed to find an equaliser, before being punished by Brazilian midfielder Paulinho in injury time.

Earlier on Saturday, unbeaten Valencia kept pace with Barca by beating Alaves 2-1. Atletico Madrid also remain unbeaten, but dropped further points in their 1-1 draw against Villarreal.