Luton Town boss Nathan Jones has confirmed that Steven Caulker has started training with the League Two side.
Last month, Caulker was released by Queens Park Rangers with the 26-year-old not featuring in Ian Holloway's plans at Loftus Road.
West Ham United were allegedly contemplating whether to hand a trial period to the former England international, but the player has now linked up with the Hatters.
Jones has not suggested that Caulker could land a deal at Kenilworth Road, but the manager has said that the former Cardiff City man has been given a 'platform' to try to get himself fit.
Caulker has only played below the second tier of English football for one season, which came during a loan spell with Yeovil Town during the 2009-10 campaign.