document: The Blades have been interested in the 20-year-old for a number of weeks but were forced to wait for him to return to fitness after a hamstring injury.
  Riley played 85 minutes of United's 1-0 Premier League 2 victory over Liverpool on Monday.
  The full-back has made two first-team appearances for Manchester United.
  Find all the latest football transfers on our dedicated page or visit our Premier League tracker here.
summary: League One leaders Sheffield United have signed Manchester United full-back Joe Riley on loan for the rest of the season.