The Brentford manager had hoped to add Santos to his squad in time for tonights friendly and was hoping to make his signing public before the weekends opening game against Blackpool.
However the bees boss will have to look elsewhere for defenders after revealing that he failed to reach an agreement with free agent Santos and he has left the club with immediate effect.
This leaves Brentford once more in the muck with only two first choice central defenders at their disposal ahead of the season. Rosenior refused to comment on speculation that he may have to add to the loan signing of Heywood to increase his defensive options to a substantial amount but did state that he wished Santos the best and was sorry that things did not work out as he wised.
The bees manager is expected to announce his squad for tonights game with Harrow Borough later and it is expected to be an exercise mainly for youth players but some first teamers may get a run out with the start of the season closing in fast.