Barcelona head coach Xavi has claimed it is "strange" that some of his players "do not understand" the style of play he is attempting to impose.
Appointed to arrest the team's decline under predecessor Ronald Koeman, the former midfield star has struggled to reverse the problems at Camp Nou in terms of performances and results.
Barca have won just two of six games since Xavi's return to the club, while a goalless draw with Benfica and a 3-0 loss to Bayern Munich saw them fail to progress to the Champions League last 16 for the first time in 20 years.
Ahead of Saturday's game with Elche, the Catalans are eighth in LaLiga, 18 points behind leaders Real Madrid and five adrift of the top four.
Xavi has suggested part of the problem lies in his players' inability to grasp 'juego de posicion', a structured approach to play with and without the ball in which the former Spain international thrived.
However, he is refusing to give up on Barca's ambitions this season, telling reporters: "I have a lot of faith in my players, although the results are not following. We have to believe in the process.
"We're Barca and we have to compete against any opponent, regardless of injuries. We can't make excuses.
"The objective is to be in the top four and to win trophies, although the gap to the leaders is very big. We don't rule anything out.
"We need to understand the way we want to play football. It's strange there are Barca players who don't understand juego de posicion.
"This is about winning, and we're eighth in the table. We have to be positive and brave: press high, press after losing the ball, attack spaces... this is what we want."
Barca's well-documented financial problems leave them in a precarious position when it comes to bolstering the squad in the transfer window.
Indeed, amid reports president Joan Laporta had met with agent Mino Raiola to discuss the prospect of signing Erling Haaland next year, LaLiga boss Javier Tebas expressed his doubt that Barca would be able to afford the Borussia Dortmund star.
However, Xavi insisted Tebas would be as happy as anyone to see a talent of Haaland's pedigree move to Spain's top flight.
"In these moments we have a difficult economic situation, and you have to think that it's not going to be easy. We have a salary cap," Xavi said.
"In terms of names, we haven't spoken of that possibility. It would interest [Tebas] for players like Haaland to be here for the good of the league."
It has been suggested Barca could look to offload Ousmane Dembele to fund January arrivals, but Xavi appeared keen to keep the winger, whose contract expires at the end of the season.
"I spoke with him yesterday. I'm positive. He wants to continue. I can't say more; it's a matter of reaching an agreement.
"He already knows the importance he'll have if he stays with us. He looks good, he's playing more and more. He's a footballer capable of making a difference."