Barcelona are confident they will be able to sign players this summer, and have reignited their move for Chelsea defender David Luiz. The Catalan giants have Vice President Manel Arroyo working on an appeal to the year-long ban imposed by FIFA for breaching rules on the transfer of under-18 players. And Camp Nou directors are now so convinced of at least a temporary reprieve that they are actively negotiating for players once again. The move of Borussia Moenchengladbach goalkeeper Marc-Andre Ter Stegen is virtually certain, while Barca have made contact once again over buying David Luiz from Chelsea. £25million should be enough to bring the Brazil international to the Camp Nou, with the Blues not averse to his departure this summer. It will be a summer of "significant change" for Barcelona, with coach Gerardo Martino leaving in the summer having provisionally agreed to replace Alejandro Sabella as Argentina manager - as revealed by MirrorSport last month.