Barcelona defender Thomas Vermaelen has insisted that his team will need their full complement of centre-backs in order to be a success this season.
Javier Mascherano and Gerard Pique are seen as the first-choice centre-back pairing at Camp Nou, but Marc Bartra and Jeremy Mathieu can also play in the heart of the back four.
Vermaelen, who is another competitor in that position, has said that "all the squad" will be needed as the season progresses.
"Defending is about a team, the shape of the team. It's an important part of the game," Vermaelen told reporters.
"I agree there are a lot of players who can play [at centre-back]. But we know there are a lot of games and we need all our players, all the squad.
"I think we all want to play the same, we want to fit into the role as well as we can with the qualities we have. We all want to play with the ball, as Barcelona does."
Barcelona are currently preparing for Wednesday's Champions League Group E clash against BATE Borisov.