Sunderland have agreed to allow full-back Craig James to remain with Darlington for a second month.
The 21-year-old has made five appearances since joining the club on loan in November.
And Sunderland boss Mick McCarthy has allowed the player to extend his stay at the Reynolds Arena.
Meanwhile, a number of clubs are monitoring the progress of Bristol City striker Lee Matthews, who is currently on loan at Darlington.
The 24-year-old is out of contract at the end of the season, which has attracted the attention of several clubs, including Second Division Swindon Town.