Barcelona’s Patrick Kluivert (right) being stopped by Valencia goalkeeper Santiago Cañizares in Barcelona Saturday. Cañizares was sent off for this foul. (Reuters)

Madrid: Real Sociedad strengthened their position at the top of the Spanish first division on Saturday with a 1-0 win at home to Celta Vigo, while a shambolic Barcelona side went down 2-4 at home to 10-man Valencia.

Javi de Pedro got the only goal for the league leaders 20 minutes into the second half, with the Basque side’s Dutch goalkeeper Sander Westerveld saving a penalty 10 minutes from time to safeguard the win.

The result took unbeaten Real Sociedad four points clear at the top, although Real Madrid can cut that advantage back to a point with victory at home to Atletico Madrid.

Valencia, the reigning league champions, raced into a 2-0 lead against Barcelona with goals from Pablo Aimar — following a comic piece of Barcelona defending — and John Carew.

The Catalans hit back with a Thiago Motta strike on the break and a comeback looked on the cards when Valencia ’keeper Santiago Canizares was sent off for bringing down Patrick Kluivert outside the box a couple of minutes before half-time.

Louis van Gaal’s side pressed hard in the second half but they were frustrated by the outstanding Valencia backline and the visitors added a third when Carew robbed Carles Puyol and passed for Fabio Aurelio to thread in six minutes from time.

As Barcelona piled forward in desperation, Valencia hit on the break through Francisco Rufete to make it 4-1 on 89 minutes.

There was still time for Kluivert to reduce the arrears with a precise finish but that late goal did nothing to dampen the angry whistles from Barcelona fans at the end of the game.

With 18 games played, Real Sociedad lead the standings with 40 points, followed by Real Madrid on 36 and Valencia on 32.

Barcelona are in ninth place, 17 points behind the leaders and just five points clear of the relegation zone.

No wonder Van Gaal was greeted with angry whistles from the Nou Camp crowd and further calls for his resignation.

Van Gaal not to quit

The Dutch coach, however, pledged to stay on. He also ruled out signing any new players during the European transfer window.

“We’re in a delicate situation,” Van Gaal said after a lengthy meeting with club president Joan Gaspart after the game.

“I’ve spoken to the players, the president, the technical staff and the medical staff and we’ve pledged to do everything possible to take the team forward. We’ve also decided that Football Club Barcelona will not sign any new players because we have confidence in the current squad.

“We lost tonight in a manner that is not acceptable,” Van Gaal said. “We started badly and then we were playing 11 against 10 and still couldn’t win. Any word I could say about the game would be one word too many.”