The 22-year-old, capped by Wales, has struggled to hold down a regular first-team place with the Millers
"We have six midfielders, two playing, two on the bench, two not getting a game, and he's in that category," boss Ronnie Moore told BBC Radio Sheffield.
"Every player dips in form but he is a quality player and I do not think we have seen the best of him," he added.
"He's got to knuckle down. He cannot get a game here and I've spoken to some clubs and let them know he is available for loan."
Source: BBC Sport