The Community Shield has not been good to Rafael da Silva; in 2011 he suffered a dislocated shoulder against Manchester City and yesterday against Wigan he was taken off early with a suspected hamstring injury.
It could leave him out for around a month, so how should United look at replacing him during that period?
Here are five options at their disposal...
Phil Jones is United's Mr. Versatile and has proved his capability racing up and down the right flank on a number of occasions over his first two seasons. He is often thought of as too talented to leave out of the side, and with Ferdinand and Vidic likely starters at centre-back, this could be an ideal situation for him to get an early run of games.
Chris Smalling has played for United at right-back on several occasions before, even featuring for England in the position. He needs regular football more than Jones after his string of injuries and this could be a test for him to prove his fitness to David Moyes.
Fabio da Silva
Fabio da Silva has played at right-back in a Champions League final for United, and would have no qualms about switching from his natural left-hand side if it means getting some match time. He played in the position in pre-season and for obvious reasons is a natural replacement for his twin brother. However he was not even on the bench against Wigan, possibly a poor reflection on his chances of starting against Swansea.
Antonio Valencia has just 'given up' his number seven shirt, for reasons yet to be clarified, and now has a chance to show just what a team player he can be. Valencia may be a natural winger but has performed solidly at right-back for United in the past when called upon and is unlikely to let them down, while providing an attacking outlet from the position Jones or Smalling simply can't replicate.
United's only pre-season signing so far made his under-21 debut last week, and that is where he is expected to remain for the time being. The 20-year-old Uruguayan would really be thrown it at the deep end if he were called upon. It's the unlikeliest of the five but still a possibility if he impresses David Moyes in training.
Who would be your choice?