Barcelona’s faint hopes of catching La Liga leaders Real Madrid suffered a huge blow as they slipped to a shock 1-0 home defeat by relegation-threatened Cadiz on Monday.

Real’s last-gasp victory at Sevilla on Sunday extended their advantage over Barca in second to 15 points, but Xavi Hernandez’s in-form side were expected to close the gap by beating Cadiz at Camp Nou.

The hosts never really got going, however, in front of a disgruntled crowd and Cadiz had the better first-half openings with Lucas Perez missing a glorious opportunity to break the deadlock. Cadiz kept coming after the interval and Perez scored in the 48th minute before the visitors wasted further big chances to extend their advantage.

Barca piled on the pressure but lacked that killer pass as they slipped to a first defeat in 16 La Liga matches stretching back to December. They remained on 60 points from 31 games, 15 behind Real who have one hand on the trophy needing seven points from six matches.

“We had the chances, more than enough to take the three points, but we have to rise from this and think about the next games,” Xavi said. “We have to change our form as soon as possible. We have got back into the Champions League places but we have to keep going.

“It’s a very bad week for us and we need to change the dynamic as soon as possible.”

The game was played in a muted atmosphere after a group of Barca fans boycotted in protest against the club’s decision to allow some 30000 away fans tickets to last week’s Europa League match against Eintracht Frankfurt, which they lost.

Aside from that shock defeat, Barca have enjoyed a revival under Xavi in recent months to climb back into the title race. Not only had they gone 16 matches unbeaten in the league, they had won their previous seven La Liga games in a row, scoring 22 goals.

Other than Ousmane Dembele’s shot, they did not look like scoring in the opening period, with Cadiz, looking for their first-ever win at Camp Nou, much the better side. The win took Cadiz to 31 points, two clear of the relegation zone.

Barcelona have now lost two home games in a row for the first time since 2003.

Felix injury

Atletico Madrid forward Joao Felix said he will miss the remainder of the season after picking up a hamstring injury during Sunday’s 2-1 La Liga win over Espanyol. Felix has scored 10 goals in all competitions for Atletico this season.