Xavi has urged Barcelona to “recover our ideology” before beginning a critical week of their season.
Barcelona have three home games in the space of six days, starting against Athletic Bilbao in LaLiga on Sunday.
Shakhtar Donetsk provide Champions League opposition on Wednesday and Real Madrid make the trip to the Nou Camp next Saturday for the first El Clasico of the season.
As LaLiga returns following the international break, leaders Real held a three-point advantage over Barcelona.
“At the start of the season, we’ve had some great moments of playing well,” said Xavi, whose side have dropped points in two of their last three league games with 2-2 draws against Mallorca and Granada.
“We must recover our ideology and get the three points by playing well.
“We are in a situation with a lot of absentees, but it won’t be an excuse for the game and to be able to play well.”
Alejandro Balde and Lamine Yamal have both been declared fit for the Bilbao clash.
But Frenkie de Jong, Jules Kounde, Pedri, Raphinha, Robert Lewandowski and Sergi Roberto remain unavailable.
Lewandowski, Barca’s top scorer with six this season, is closing in on a return after ankle trouble and Xavi said the Poland forward “has a very good feeling” of returning against Real Madrid.
Xavi said: “He’s a great leader and always goes forward, he wants to be there and he’s hurting less and less every day.
“He has a very good feeling. He always pulls himself forward.
“But there is a lot of variety (in attack) and people with confidence in front of goal. That is great. Last year, we depended a lot on Lewandowski.”
On the potential return of other individuals, Xavi added: “The player’s feelings will tell when he will arrive. We won’t force anyone.
“Feelings are the key and they will mark the return of all of them.”
Bilbao began the weekend in fifth place, four points behind Barcelona after beating Almeria 3-0 before the international break.
The Basques side are managed by Ernesto Valverde, who won two LaLa titles and a Copa Del Rey during his time in charge of Barcelona between May 2017 and January 2020.
Xavi said: “Athletic are very strong physically and technically gifted. Valverde is a great coach and likes to press high.
“I’m expecting a difficult opponent, we have some injuries but that’s no excuse and we need our fans.
“We’re three points behind the leaders. But we have to keep working hard, to keep fighting, and to keep improving, because there is a long way to go in LaLiga.”