Barcelona sporting director Andoni Zubizarreta has refused to rule out more movement in the transfer window, saying "anything could happen".

The Catalan giants completed the signing of Arsenal defender Thomas Vermaelen earlier today on a five-year deal worth around £15m.

He joins Luis Suarez, Ivan Rakitic, Claudio Bravo, Marc-Andre ter Stegen and Jeremy Mathieu as new recruits at the Camp Nou this summer, as Barca look to reclaim their La Liga title back from Atletico Madrid this coming season.

"With the addition of Thomas we completed a defensive line of a very high level," Sky Sports News quotes Zubizarreta as saying. "There are options that we are working on for the exit of some player, as such we're not discarding that others could come in.

"What I can say is that at midnight on August 31 we hope to have the best squad possible. Even though we are very happy with the players that we have, if there is a chance to improve it, we will try. Until the first or second [of September], when we talk about the market being closed, anything could happen."

Barcelona kick off their league campaign with a home match against Elche.