Gareth Bale has given a strong indication that he expects to remain with Real Madrid next season.
Bournemouth have signed Artur Boruc on a permanent deal following his release by Southampton.
The 21-year-old Cameroonian has been training with Rovers for the past month and has signed a two-year deal after impressing in pre-season friendlies against Wrexham and Portimonense.
Songo'o, who is the younger brother of former Sheffield Wednesday loanee Franck, started his career in Spain before moving to MLS side Sporting Kansas City, where he was released from this summer.
Rovers boss Gary Bowyer has made strengthening his back line a major priority and adds Songo'o to a defensive pool including fellow new signings Tommy Spurr, Matt Kilgallon and Todd Kane.