Real Madrid are now four points clear at the top of the table.
“If one has to be sincere, La Liga is almost impossible," said the Uruguayan forward to Sport.
He said Barca had lost it from their own mistakes.
“It's clear the game against Sevilla is a game it that makes everything hard for you. We had options to go ahead, that day was important, but in Vigo it was key. We lost our big chance. If we had beaten Celta, we would have been better against Atletico.
"The blow was in Vigo, the late goal from Aspas. It hurt. Now we have to finish (the season) well and go for the Champions League."