Logan played three times for City before being released this summer
Brentford have signed former Manchester City full-back Shaleum Logan and German defender Marcel Eger from Bundesliga side St Pauli.
Logan, 23, who spent the 2009/10 season on loan at Tranmere, has signed a one-year deal with the League One club.
Eger, 28, has agreed a two-year contract at Griffin Park, with a further year's option.
He has spent the last seven years with St Pauli, twice captaining them to promotion to the Bundesliga.