Mullan showed a great deal of promise in United's reserves

The 19-year-old winger has agreed a short-term deal with Dale following a trial spell at Spotland.

Mullan impressed in United's reserves but has been without a club since leaving Old Trafford in the summer.

He previously had trial spells with Leeds, Huddersfield and Swansea before linking up with Rochdale and playing a number of reserve games.