I think Chambers should play. It seems highly unlikely that we'll make it through the whole season, or even to January, without having to utilise the full squad at some point. It would be a far worse thing to have to call on Chambers in say December, having not played since the Legia game.
Bailey, Duran, McGinn, Pau, and Digne are also on the graphic, so if we're assuming it reflects selection we're looking at some combination of Chambers, Pau, Digne and ? across the back. Bailey, McGinn, ?, ?, ? in mid. And Duran up front.