Pellegrini felt they deserved more for the performance on the day.
He said afterwards: "We lost two points. I'm very bitter about the result. We had four very clear chances, we didn't convert them, we played at home and they tied a game that we deserved to win by a wide margin.
"I don't care who we played, I'm interested in how the team played and I'm very happy about that, but we lacked the precision to finish off the chances we created. Barcelona hardly got close to our goal, a goal that I don't know if it was offside by half a centimetre, but we had the dominance, tension and attack that we need to play this type of game.
"We played a very complete game in terms of performance. Barcelona, despite being difficult offensively, rarely got to our goal. Fran didn't have any important interventions and their goalkeeper did have many. We created a number of chances that are not easy to do against Barcelona and unfortunately we conceded two goals again. In general terms, I am very happy with the team's performance and I am very bitter about the result.
"We urgently needed a performance like today's, to return to being the attacking team, the aggressive team that we were for most of the championship until the FIFA break where we went seven games without losing, we beat Atlético de Madrid and Osasuna with good results, and unfortunately we didn't capitalize on the chances we created. The team has to regain confidence with today's performance and hopefully get the three points."
Pellegrini also said: "The most important thing is that we got the team back into shape, we hadn't been able to in the last few games and that makes me very happy. The bad results we were experiencing made one rush to make a decision. You're left with the glass half full, very happy with the team's attitude, the football and very bitter with the result even though it's Barcelona because we deserved better luck."
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