"But this is football, and we have to go out there to win the next match and think about how we can continue to improve".
Atletico entered the match with the best defense in La Liga with only 11 goals previously conceded.
Barcelona's players returned to training on Friday (2 March) only hours after their disappointing 1-1 draw at Las Palmas in order to begin the preparations for the crucial visit of second-placed Atletico Madrid.
Barcelona was 11 points ahead of Atletico a few weeks ago, but Simeone's team has been thriving.
For all Atletico's discipline and defensive rigour, one mistake in the 26th minute was all it needed.
Griezmann will be the main threat to Barca on Sunday with the French striker hitting his best form of the season netting seven goals in his last two appearances as his partnership with Diego Costa is beginning to flourish.
"It will be an attractive match in which the three points will be worth a lot", Barcelona coach Ernesto Valverde said Saturday.
Will Donald Trump's tariffs decision trigger global trade war?
This is now going to give us an opportunity to potentially reopen facilities and grow new business", Frabotta said. The US imports steel from more than 100 nations and brings in four times more steel from overseas than it exports.
Atletico are doing well now, but they have been doing well since the beginning of the season.
Jose Mourinho has already denied United will look to spend big on another attacker this summer, but the club is believed to be desperate to partner Paul Pogba with Griezmann.
Another stellar performance by Griezmann would come in handy for Atletico. There were reports he received many offers to leave Atletico in the most recent transfer window, including from Barcelona.
"I really want to score and celebrate it on Sunday", he said.
Simeone recently said Atletico fans should do everything possible to try to keep Griezmann in the club for as long as possible.
Luis Suarez thought he had scored a second after half-volleying through Oblak's legs but was flagged offside, before Jose Gimenez applied a crucial block to deflect a Messi shot over.
But the centre-back appeared to be fully fit in the video released by Barcelona during Friday's workout and should be ready to lead Valverde's defence when Atletico visit the Nou Camp in a clash which could be key in the race for the title.