Xavi warned Barcelona they cannot consider the league title won even if they beat Girona to open up a 15-point lead over Real Madrid on Monday.
Barca were crushed 4-0 by Madrid in the second leg of their Copa del Rey semi-final in midweek, meaning the Blaugrana only have the LaLiga title left to play for.
They were already 12 points clear at the summit before this weekend, and Madrid's surprise 3-2 home defeat to Villarreal on Saturday gives Barca the opportunity to increase the gap.
No team has ever overturned such a deficit at this stage of a LaLiga season, so Barca's position looks very secure.
But Xavi was keen to stress the importance of not taking their lead for granted, with the former midfielder acknowledging his young squad does lack a degree of maturity.
"[The title] wouldn't be considered won, there would still be 10 [games] left," Xavi bluntly said in his pre-match press conference.
"When the league is won, we'll celebrate it. We have to win it. Tomorrow's game is a very good test for us after the elimination in the Copa.
"We depend on ourselves. Fifteen points would be a spectacular difference. It wouldn't be all done, but it would be a big difference, and winning the league would be extraordinary."
Despite Barca's massive lead in LaLiga, their performances in other competitions have left a lot to be desired.
While they did win the Supercopa de Espana, Barca dropped out of the Champions League at the group stage and into the Europa League – Manchester United deservedly eliminated them from that competition, and they were even more comprehensively dumped out of the Copa by Madrid.
But Xavi lent on comments once made by former Madrid boss Zinedine Zidane as he suggested LaLiga success reflects stability.
Asked what incentives Barca players have, Xavi said: "Winning LaLiga. Winning LaLiga is the focus.
"We have won five Champions Leagues, and winning the Champions League is required of us, but winning LaLiga gives us stability.
"We are 12 points ahead and that means that we do things well. We value what we are doing. It's amazing, and gets us closer to winning LaLiga, which for us would be extraordinary."
As for the other competitions, Xavi reminded critics they are still during the early stages of a new era.
"We need time. We won the Supercopa, we are on track in LaLiga. In Europe, we have not competed well.
"We've signed players, there are youngsters [in the squad]... when we have been playing together for two or three years, we will not be under construction.
"We've won a title and we're on our way to another."