Barcelona have failed to win any of their first three away games for the first time since 1994-95.
Luis Suarez says Barcelona have a "tough year ahead" following their worst league start in 25 years.
The Catalans fell to their second defeat of the 2019-20 campaign at Granada on Saturday and they now sit in seventh spot in the LaLiga table after securing seven points from five games.
"It's a worrying defeat, a defeat that hurts," Suarez told AS. "And it's a defeat that we have to take a real good look at. There are lots of things that we have to improve.
"There's a long way to go yet, but these are the types of games that win you the title.
"We have to be tougher if we're going to win the league. We have a tough year ahead of us."
The LaLiga champions haven’t been able to seal three points away from the Camp Nou since April, and the former Liverpool striker says Ernesto Valverde needs to change tactics when they are on the road.
"What we have to look at is the way we're playing as the away side, because the lack of cutting edge and chances is worrying," Suarez added.
"We're Barcelona, and we have to go out there to win the game - we can't start the way we did."