Luis Enrique has ordered his Barcelona players to cut out the mistakes after witnessing a shocking capitulation against Athletic Bilbao, shattering their hopes of winning six trophies in 2015.

The Catalan giants have already lifted the La Liga, Copa del Rey, Champions League and UEFA Super Cup trophies, and were gunning to add the Supercopa de Espana before finishing the year with the FIFA Club World Cup in December.

But a humiliating 4-0 thrashing against Athletic on Friday night has all but destroyed those dreams, as well as leaving unexpected question marks against Enrique’s all-conquering team ahead of next weekend’s La Liga kick-off.

Friday’s loss came hot on the heels of Tuesday’s UEFA Super Cup victory over Sevilla, which saw Barca squander a 4-1 lead before eventually prevailing 5-4 after 
extra time, and the majority of the eight goals conceded by Enrique’s men over the two games were the result of individual errors.

Goalkeeper Marc-Andre ter Stegen was the first culprit in Bilbao, needlessly racing out of his goal to attempt a headed clearance which dropped to Mikel San Jose, who opened the scoring with a stunning half-volley which has been measured at 47.5 metres.

Inexperienced midfielder Sergi Roberto, who struggled throughout the game, was the next offender, losing possession close to the edge of the area to allow Aritz Aduriz to score the first goal of his hat-trick.

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And then Dani Alves, another player who performed well below par, made an almighty hash of an attempted clearance from a cross, succeeding only in playing the ball back across goal for Aduriz to net again.

After witnessing similar individual errors against Sevilla on Tuesday, Enrique has told his players that enough is enough.

“Of course I’m worried,” he said. “I am concerned that we are letting in so many goals and it’s an issue that we will correct.”

Urging his players to regain last season’s standards, which saw them concede a league-low 21 goals in their 38 La Liga outings, he added: “Football is a game of mistakes but we have gone from being the team to concede the least amount of goals to being a side which lets them in too easily.”

However, Enrique also claimed that he has not given up hope of overturning the four-goal deficit in tomorrow’s second leg.

“If there’s any team which can come back from this, it’s Barca,” he said. “With our fans behind us, we hope that we can get an early goal. We are going to try with all our strength.”

Enrique also accepted his share of the responsibility after fielding a makeshift line-up including a midfield trio of Javier Mascherano, Roberto and Rafinha who had 
never previously played together.

“I made rotations and I accept responsibility for the defeat, but this is not the time of year to be tiring out the players,” he said.

“Some of them played for two hours on Tuesday and, as the coach, these are the decisions I have to take.”