Barcelona were held 0-0 by Rayo Vallecano in their opening game of the La Liga season and had captain Sergio Busquets sent off late on.
The Catalans had 21 shots on goal and the majority of possession at the Camp Nou but were unable to break the deadlock.
Barca boss Xavi started close-season signings including defender Andreas Christensen, winger Raphinha and striker Robert Lewandowski, who were only able to feature after being registered with the league late on Friday.
The five-time Champions League winners had to comply with La Liga’s strict financial controls before being able to confirm the likes of ex-Bayern Munich attacker Lewandowski in their squad ahead of the new campaign.
“We could have won, but now we have to correct our mistakes and think about Real Sociedad next weekend,” said Barcelona defender Eric Garcia.
“We wanted to start the season on the right foot and with a victory, but we knew that Rayo gave us a lot of problems last year. They were good defensively tonight.”
The hosts dominated the opening half an hour as Lewandowski was denied a goal on his competitive debut.
The Poland forward was judged to be offside from an Ousmane Dembele pass before his delicate chipped finish was cancelled out.
As rain fell at the Camp Nou, Pedri came close to breaking the deadlock with 10 minutes of the half to play but his curling effort flew past the post.
Xavi’s side ended the game with 10 men as club skipper Busquets was red-carded for an elbow on Falcao in the fourth of eight injury time minutes.
Less than 60 seconds later, Falcao thought he had scored the winner, and claimed Rayo’s third straight win over the Catalans, but was found to be offside and the visitors held on for the point.
Ancelotti to retire after Real Madrid spell
Carlo Ancelotti confirmed on Saturday that he will quit football management when he eventually leaves Real Madrid, ending one of the most glorious careers of football’s modern era.
Ancelotti had said in May that he would “probably” quit once he left Madrid, but he removed all doubt in an interview with Italian daily Il Messaggero.
“This time at Real will end my career, after Los Blancos I will quit,” said the 63-year-old.
“Real are the very top of football. It makes sense to call it quits after my experience here.”
Ancelotti became the first ever coach to win all five of Europe’s top leagues when he claimed the Spanish title last season, and he capped a remarkable campaign by winning his second Champions League for the club.
That was the 14th time Madrid had been crowned European champions and was the latest in a string of honours the Italian has won in a long career as player and coach.
He won three Serie A titles with Roma and AC Milan in the 1980s, as well as back-to-back European Cups with Arrigo Sacchi’s Milan in 1989 and 1990.
He returned to Milan as coach in 2001 and in eight years at the San Siro won the 2004 league title and two Champions Leagues.
He also led Chelsea to a league and FA Cup double in 2010, setting a Premier League record of 103 goals scored in the process.
He also won Ligue 1 with Paris Saint-Germain in 2013 and the Bundesliga with Bayern Munich four years later.
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