Even his biggest fan would admit that despite encouraging moments, he did not further his claims to usurp Patrice Evra as United's first choice left-back.
In fact he was even jumped in the queue by new addition Alexander Buttner, and Evra answered his critics with a fine season.
David Moyes is even said to have bid for Leighton Baines, asking questions of all three of United's potential left-backs.
Fabio was the only to get on the scoresheet during pre-season, doing so when playing from a right-back role.
A hint at what is to come over the coming season? It would make sense.
But he lacks true competition at right-back, with alternatives tried out in Phil Jones, Chris Smalling and Antonio Valencia only stopgaps at best, being an unnatural position for all three players.
In Fabio, David Moyes may have the answer.
New signing Guillermo Varela is too raw to be thrown in, and could even go on loan, while Beligan youngster Marnick Vermijl says he aims to make an impact this season, it's hard to see him displacing Rafael.
Fabio is a player who potentially could, for he has shown he can do it before.
When Manchester United had their run to the Champions League Final in 2011 it was Fabio who was the first choice right-back, impressing with his runs forward as much as his defending.
Originally the twin who was tipped for greater things, Fabio has played second fiddle to his brother largely through his Old Trafford tenure despite that 2011 run, with niggling injuries holding back his development.
He might just provide the most natural deputy for Rafael in the position, able to implement similar traits as well as an identical appearance.
Given the opportunity can he displace his brother? We shall see, he will have to step his game up considerably as Rafael has improved vastly over the past 12 months, but if right-back does transpire to be his eventual position, it will be fascinating to see how the battle plays out over the course of the season.
image: © wonker