Barcelona coach Xavi Hernandez said Saturday he is convinced his team can fight back and defend their league title despite the negativity around the club.

The Catalans won La Liga last season but are fourth, eight points behind leaders Girona and seven off second-place Real Madrid.

Barcelona visit Real Betis on Sunday before a tough trip to face Athletic Bilbao in the Copa del Rey quarter-finals.

After Real Madrid thrashed Barcelona last Sunday in the Spanish Super Cup final, Xavi's team has come in for heavy criticism.

"We are optimistic, we know these seven or eight points we can make up," Xavi told a news conference.

"Tomorrow we will try to play our football, using our idea of the game, there's the whole second half of the season to go and we have the most hope possible."

The coach said he was extremely positive in life, even though many around the club and in Catalonia typically have a more negative outlook.

"(Positivity) is what's lacking most, but I counter that," continued Xavi.

"Catalans, the club, its history, we are sufferers ... I see (these tough games) as an opportunity.

"As I've been a player and won a lot, I am calmer, but I also lost a lot -- Barcelona have not always won.

"The level of demand on us, we accept, but a lot of the time positivity is lacking."

Xavi admitted his team need to tighten up at the back and finish more of their chances, but insisted he believed the team can triumph this season.

"It's about attitude, I always look at things positively ... I wake up positive, I'm made like that," he added.

"Barca, in some ways, everything around the club, isn't like that.

"We can achieve things this season and we will fight, and if not, we will have tried -- failure is not trying."

League leaders Girona welcome Sevilla on Sunday while Real Madrid host bottom of the table Almeria.