By Ewan Murray The mood around Old Trafford will feel significantly different on Sunday afternoon as the beginning of a new era approaches. Erik ten Hag’s dismissal last Monday was hardly surprising and the Red Devils have swiftly appointed his successor. Sporting CP boss Ruben Amorim will take charge of his first match after the November international break, with Ruud van Nistelrooy – who oversaw a 5-2 Carabao Cup win midweek \- leading the side until then. Chelsea will face a buoyant Old Trafford crowd this weekend but will take solace in the knowledge that they won’t be battling a full-stre…