Craig Alcock has completed his permanent switch from Sheffield United to Doncaster Rovers
The 28-year-old has signed a two-and-a-half year contract at the Keepmoat after impressing during his initial loan spell.
The defender has been on loan at the Keepmoat for the last two months but it has long been expected that the deal would be converted to a full transfer during January.
Alcock found first team opportunities limited with United with John Brayford, Kieron Freeman and Kieran Wallace all ahead of him in the pecking order while boss Nigel Adkins has been keen to drastically reduce the size of his squad.
By joining Rovers, Alcock reunited with Ferguson whom he previously worked under at Peterborough United, the club he left to join the Blades.
The 28-year-old has made ten appearances so far for Rovers.