United have agreed to allow Davide Petrucci to stay with Peterborough until the end of the season.
The 21-year-old has only featured twice since joining the Championship club on loan due to the bad weather and FA Cup but is likely to have a key role to play in the remainder of the campaign.
Posh are currently bottom of the table but a win in their game in hand would take Darren Ferguson's side above Bristol City and Barnsley.
Petrucci, who is getting his first taste of first-team football, is one of two Reds at the club with centre-back Scott Wootton completing his second stint at London Road.
"The ones I brought in have made a difference," commented Darren Ferguson to Posh Player. "Wootton and Petrucci were a no-brainer coming from there [United] because they are good players."
The creative midfielder added on Peterborough's official website:" I am very happy. I only signed for a month in the first place because it was my first loan spell. I didn't know what to expect.
"However, since the first few days, I realised that I wanted to stay for longer and I am very pleased to be here until the end of the season."