BARCELONA (REUTERS) - Iago Aspas scored twice as Celta Vigo sent Barcelona crashing to a 4-1 defeat to go top of La Liga ahead of Real Madrid's clash against Athletic Bilbao later on Wednesday.

After disappointing spells at Liverpool and Sevilla, Aspas is back to his best this season having returned to Celta and struck clinical finishes in either half against a Barca side who were far from their normal dominant selves.

Nolito, a former Barca youth player, fired his fifth goal in as many games to put Celta ahead after 25 minutes with a pinpoint curling drive from the left of the area.

Aspas then chipped the ball over keeper Marc-Andre Ter Stegen for the second minutes later.

It was clear that it was not going to be Barca's day when Lionel Messi struck the woodwork after 52 minutes with only keeper Sergio Alvarez to beat and then Aspas raced clear and slotted home on 55 minutes.

Barcelona's Neymar scored from a tight angle after 80 minutes but Celta substitute John Guidetti volleyed in their fourth minutes later.

Celta lead La Liga with 13 points, one more than Barca after five games, while Real are on 10 points having played one match fewer.

The players in the blue of Celta could have been mistaken for Barca the way they pressed the visitors back with their quick movement and link-up play.

Ter Stegen could only get his fingertips to Nolito's strike into the top corner and then Gerard Pique hesitated in possession on the halfway line with the ball finding its way to Aspas who ran through and lifted the ball over the keeper.

After the break Barca pressed forward but left themselves wide open at the back. Messi hit the woodwork and then shortly after Aspas latched onto a long punt forward, evaded a challenge from Dani Alves, and found the corner with his shot.

Messi set up Neymar for a consolation while Guidetti was then given space in the area and cracked the ball home.