By Felix Keith Manchester United were beaten 3-1 by Burnley in a behind-closed-doors friendly at their Carrington training ground on Wednesday. United face Newport County in the fourth round of the FA Cup on Sunday after a two-week break in their schedule. The winter break was established by the authorities in order to give players some time off and minimise the number of injuries. It has been useful for United, who have been able to usher back some of their absentees in the period following their 2-2 draw against Tottenham in the Premier League on January 14. Luke Shaw, Harry Maguire, Lisandr…