Barcelona's painful reverse to archrival Real Madrid in Wednesday's King's Cup final brings to an end a hellish week and leaves it facing its first season without major silverware in six years.

Coach Gerardo Martino, in his first term in charge at the Nou Camp, was defiant after the 2-1 defeat at Valencia's Mestalla stadium and suggested he intends to see out his contract, which runs to the end of next season.

A week ago, Barca was well placed to repeat its record treble of La Liga, Champions League and King's Cup from 2008-09 but is now likely to end the campaign with nothing more than the season-opening Spanish Super Cup.

It was dumped out of Europe's elite club competition by Atletico Madrid last Wednesday and crashed to a shock 1-0 La Liga defeat at Granada on Saturday that left it four points behind leader Atletico with five games remaining.

"I am in profound pain because of the defeat and for the people who support us," Martino said at a news conference after Gareth Bale scored a brilliant 85th-minute winner for Real in the latest 'Clasico' between the Spanish giants.

"This team has a long way to go and many positive things still to achieve," said the Argentine.

"I am feeling as I have to feel in these situations when you suffer a defeat like this.

"I can't imagine a defeat more painful but my future does not depend on this result.

"As I have been saying in recent weeks, I don't think my future will change because of everything we have lost, just as it wouldn't if we had won."

Martino's immediate task is to lift the players, the majority of whom will be heading to the World Cup finals in Brazil starting in June, for the La Liga final run home, starting with Sunday's match at home to fourth-placed Athletic Bilbao.

"It has been a very hard week for us on all fronts but we have to pick ourselves up and keep aspiring to what we have left," Martino said.

"We have to find the strength where it is now scarce. The league is not going in our favor but have to fight to the end because we have a right to, that is what the maths says, but we cannot deny it has been a hard week.

"Today was a tough blow, our expectations for the match were very high.

"When you lose it is very difficult to single out players, I want to focus on the football the team played.

"Maybe we lacked depth but we had a lot of control. When we had the game in our grip we were hit on the counter and that made us lose the match."