Xavi Hernández said Saturday's crushing 4-2 defeat at Girona was emblematic of Barcelona's shortcomings this season, but insisted his team have been the better side in their four games against their Catalan rivals and Real Madrid.
Girona's win at Montilivi sealed their place in the Champions League for the first time the Catalan club's history, while it also meant Madrid were crowned LaLiga champions with four games to spare.
- Stream on ESPN+: LaLiga, Bundesliga, more (U.S.)
Barça, meanwhile, have dropped to third in the table, below Girona, and with a second-place finish and a spot in next season's Spanish Super Cup now out of their hands.
"I am really sad and disappointed because we have seen both sides of the coin in one game," Xavi said in his post-game news conference.
"I was very satisfied at half time because we pressed well and dominated Girona, which is very difficult, perhaps until the 60th minute. From there, it's the summary of our season.
"We were not clinical. If we get the third goal, it changes the game. I don't know how many chances we created, but enough. We need to be more effective in the final third.
"And then it's about mistakes. We had the game under control, but once again it comes down to errors."
Andreas Christensen and Robert Lewandowski had given Barça a 2-1 lead at the break, with Girona responding through LaLiga's top scorer Artem Dovbyk.
However, the game swung in the second half thanks to goals from Miguel Gutiérrez and a brace from substitute Portu in the final 30 minutes as Girona booked their place in next season's Champions League.
Barça have now lost both league games against Girona this season for the first time, conceding eight times in the process, while they were also beaten in both El Clásico fixtures against Madrid.
However, Xavi said he believes the results did not reflect the balance of play in those matches.
"In the four games against the two teams above us, Madrid and Girona, we have been superior," the Barça boss insisted. "But it is not reflected in the scoreline and we have lost all four, so we have to improve a lot."
Barça's season will end trophyless but they are still competing for second place with Girona and a place in next season's Super Cup -- and the cash boost that comes with the four-team tournament that is played in Saudi Arabia.
"We will give our all to win these final four games and finish second, but it is no longer in our hands," Xavi added.
"We have to compete better. The first hour, for me, was very good. The last 30 minutes were not at the level required from these players or this club.
"The team tried until the end, but we lost our order after the goals. When you see the scoreline is 4-2, it's not easy to digest. We need to pick the team up mentally and go again."