The 21-year-old, who is yet to feature under Martin O’Neill this season, is looking forward to get valuable first-team action at Middlesbrough.
“I’m very happy to be here,” said Osbourne. “Middlesbrough feels like a Premier League club, while I’m looking forward to working with Gordon Strachan.
“Before coming here, I first spoke to Martin O’Neill and Stiliyan Petrov about the gaffer and they both spoke highly of him.
“I’m here for two months and right now I’m looking no further than that but hopefully I will play a few games and can help the team.
“I played for Forest in the Championship last season so I know a little bit about what it’s about. I know it’s a lot quicker than the Premier, that’s for sure!”
