Fabio looks certain to leave United this summer, but twin Rafael is yet to establish himself under David Moyes.
Six years ago this month, a pair of fresh-faced curly-haired Brazilian twins upped sticks from Rio de Janeiro and rocked up in chilly Manchester.
The Da Silva brothers, then just 17, were not allowed to play for Manchester United until the following campaign but there was much excitement about the pair of full-backs, excitement which increased when fans saw them play.
The pair started making waves in pre-season, but while Fabio was injured for much of the 2008/09 season, Rafael began to establish himself as an exciting attacking full-back – making 28 appearances in all competitions and scoring a memorable, if unimportant, goal in a 2-1 defeat at the Emirates Stadium.
But since then, what has changed?
Now 23, the pair have had very different careers to date. Injuries have continued to dog Fabio while despite winning many plaudits, Rafael has had fitness issues of his own.
This week rumours abound that Fabio’s United career is over after his foolish red card challenge which condemned the Red Devils to an FA Cup defeat at the hands of Swansea.
The left-back’s contract is up at the end of the season, and having made only three appearances under David Moyes, it is highly unlikely that it will be extended.
This is extremely disappointing for a player who many at Old Trafford saw as the long-term replacement for Patrice Evra.
Having failed to oust Evra despite the Frenchman's declining form, Fabio was packed off to QPR on loan for the 2012-13 season, but the move hardly worked out.
Fabio struggled with a series of injuries and only made 23 appearances in all competitions as the Hoops were relegated.
Returning to Old Trafford this season, the Brazilian has found himself not only behind Evra in the pecking order, but also the much-maligned Dutchman Alex Buttner.
It is strange now to think that Fabio started in the Champions League final at Wembley in 2011.
He ended that season with a run in the side at right-back while his brother was injured and Sir Alex Ferguson clearly had much faith to start him in the most important game of the year.
By the next season, however, things had clearly changed and Fabio only made five league appearances as Ferguson preferred Rafael, Phil Jones and Chris Smalling at right-back and Evra was virtually ever present on the other side.
Fabio was once touted as the more talented of the two brothers and it is sad to see his United career fizzling out in such a fashion.
But while his brother has a contract tying him to the club until 2016 and has made 146 appearances, 90 more than Fabio, all is not rosy for Rafael.
Despite being viewed as first-choice right-back for the last couple of years, Rafael frequently suffers minor injuries which mean he has only once made over 20 league appearances in his six seasons at the club.
Both Ferguson and Moyes have sometimes preferred Smalling or Jones, both of whom are clearly not natural right-backs, even when Rafael has been fit.
So far this season Rafael has failed to gather any form as the whole team have struggled, and he has been missing through injury on several occasions.
As Moyes looks to strengthen in central midfield and at left-back, Rafael is not exactly in a position to sit comfortably and the Scotsman may start looking at alternative right-backs too.
The Brazilian brothers both have pace, impressive passing ability and a great on-pitch work ethic, but as Fabio showed on Sunday and Rafael has in the past, both can be rash.
Despite Rafael’s increased maturity they both remain suspect defensively, a luxury United cannot afford in this transitional period.
It looks too late for Fabio, but Rafael should take note of his brother’s plight.
If he cannot stay fit, and improve the defensive side of his game, he may be following his twin out of the Old Trafford exit sooner than expected.
images: © Andrea Sartorati