Arsenal and Chelsea doing business with one another used to be on just one condition: “only if we have to”. Get the FourFourTwo Newsletter The best features, fun and footballing quizzes, straight to your inbox every week. So given that, yet again, Chelsea are looking at trimming a 41-man squad, it makes sense for Arsenal to do their rivals another favour. Really though, the opportunities lie at the back, following new manager Xabi Alonso's comments that his collection of nine centre-backs needs reducing to “four or five”. Arsenal, meanwhile, have a very clear hierarchy with Timber and Saliba as the established first-choice options in their respective positions, but it makes sense to bring in someone who could potentially challenge either within three years, while adding quality in depth now.