The Camp Nou outfit have endured a difficult season and currently sit four points adrift of leaders Atletico Madrid with only three matches to play.
Real Madrid are two points behind Barca in third, but Carlo Ancelotti's men boast a game in hand.
"We know that things are out of our hands and that it's going to be difficult, but we still have hope," he said. "We have to use every chance we have left.
"They are there on their own merit," Busquets continued. "All we can do is keep fighting to win until the last minute of the last game.
"We still have to see what happens in the league, but in terms of results it hasn't been a good season for us."
"We are people like anyone else and it was hard to play that game," he added. "But we had to put it all behind us and go out and fight for the three points.
"Tito will be on our minds in all the games we have left."
