After the club sold 24.5% of Barcelona Studios, all four of them were registered with LaLiga.

Jules Kounde has not yet been registered and won't be until Barcelona creates more salary space.

Xavi said after the game that they have time until August 31 to strengthen.

I don't want to use that as an excuse. I am aware of the high expectations. We need to analyse the game, improve and believe in the model of play.

Rayo did a good job defending. It wasn't easy for us to createchances. We wanted to show the fans that we are on the right path. We ask for patience.

Barcelona coach Xavi Hernandez instructs his players during their goalless draw with Rayo Vallecano to begin LaLiga. Pedro Salado/Quality Sport Images/Getty Images

When it comes to signing players, Barcelona are at a ratio of1:1. That makes it possible for them to spend whatever they save or make on wages.

It is necessary for other players to leave before more bodies are brought in. According to sources, Frenkie de Jong still wants to stay at Barcelona, even though he is wanted by two other teams.

Xavi says he will play a key role if he stays, but he left the door open to a transfer.

He is an important player and his role isn't as a substitute.

He came on like last week. I don't know what will happen in the transfer market, but he will be very important for us. He has an attitude that makes him stand out.

The visitors had their moments and the home goalkeeper made some important saves.

Pedri, Busquets, Raphinha and Ousmane Dembele all had chances for the visitors.

One of them was scored by Lewandowski, a 45m signing from the German club, who couldn't mark his official Barcelona debut with a goal.

"He worked for the team, gave a hand for the high pressure and his control was very good when he was the solution in the build up," Xavi said of the Polish forward.

"But we needed more effectivity today, that was the main problem, but I am really happy to have him in the squad."

Robert and everyone else are upset, but they need to believe in the process. He will score in a matter of time.